diff --git a/ARCHITECTURE.md b/ARCHITECTURE.md
index 349246d..065fb3a 100644
--- a/ARCHITECTURE.md
+++ b/ARCHITECTURE.md
@@ -496,7 +496,8 @@ sequenceDiagram
 
     CLI->>GS: report(filePath, sheetUrl, credentials, config, limit, all?, silent?)
     GS->>GS: authentication(credentials)（OAuth2）
-    GS->>Archive: getArchive(filePath)
+    GS->>Archive: getArchive(filePath) → { archive, removeSignalHandlers }
+    Note over GS: try/finally で cleanup を保証
     GS->>GS: loadConfig(configPath)
     GS->>Archive: getPluginReports(archive)
 
@@ -513,6 +514,7 @@ sequenceDiagram
         Note over GS,Sheets: silent=false 時: Lanes で進捗表示 + レート制限カウントダウン
     end
 
+    GS->>GS: removeSignalHandlers()
     GS->>Archive: archive.close()
 ```
 
diff --git a/packages/@nitpicker/cli/src/commands/crawl.spec.ts b/packages/@nitpicker/cli/src/commands/crawl.spec.ts
index f776aef..b00e4b1 100644
--- a/packages/@nitpicker/cli/src/commands/crawl.spec.ts
+++ b/packages/@nitpicker/cli/src/commands/crawl.spec.ts
@@ -177,6 +177,27 @@ describe('startCrawl', () => {
 		expect(result).toBe('/tmp/test.nitpicker');
 	});
 
+	it('完了後にシグナルリスナーが蓄積しない', async () => {
+		const { startCrawl } = await import('./crawl.js');
+		const before = process.listenerCount('SIGINT');
+
+		await startCrawl(['https://example.com'], createFlags());
+		await startCrawl(['https://example.com'], createFlags());
+		await startCrawl(['https://example.com'], createFlags());
+
+		expect(process.listenerCount('SIGINT')).toBe(before);
+	});
+
+	it('eventAssignments がエラーでもシグナルリスナーが解除される', async () => {
+		mockEventAssignments.mockRejectedValueOnce(new Error('scrape failed'));
+		const { startCrawl } = await import('./crawl.js');
+		const before = process.listenerCount('SIGINT');
+
+		await startCrawl(['https://example.com'], createFlags()).catch(() => {});
+
+		expect(process.listenerCount('SIGINT')).toBe(before);
+	});
+
 	it('イベントエラー発生時に CrawlAggregateError をスローする', async () => {
 		mockEventAssignments.mockRejectedValueOnce(new Error('scrape failed'));
 
diff --git a/packages/@nitpicker/cli/src/commands/crawl.ts b/packages/@nitpicker/cli/src/commands/crawl.ts
index e9e6380..1c654b8 100644
--- a/packages/@nitpicker/cli/src/commands/crawl.ts
+++ b/packages/@nitpicker/cli/src/commands/crawl.ts
@@ -143,13 +143,16 @@ type LogType = 'verbose' | 'normal' | 'silent';
  * crawl via {@link CrawlerOrchestrator.abort}, then kill zombie Chromium
  * processes and exit. The abort signal propagates through the dealer's
  * AbortSignal mechanism so no new workers are launched.
+ *
+ * Signal handlers are automatically removed in a `finally` block when
+ * the event assignment pipeline completes or throws.
  * @param trigger - Display label for the crawl (URL or stub file path)
  * @param orchestrator - The initialized CrawlerOrchestrator instance
  * @param config - The resolved archive configuration
  * @param logType - Output verbosity level
- * @returns A promise from the event assignment pipeline.
+ * @returns A promise that resolves when the event assignment pipeline completes.
  */
-function run(
+async function run(
 	trigger: string,
 	orchestrator: CrawlerOrchestrator,
 	config: Config,
@@ -160,16 +163,22 @@ function run(
 		orchestrator.garbageCollect();
 		process.exit();
 	};
-	process.on('SIGINT', killed);
-	process.on('SIGBREAK', killed);
-	process.on('SIGHUP', killed);
-	process.on('SIGABRT', killed);
+	const signals: NodeJS.Signals[] = ['SIGINT', 'SIGBREAK', 'SIGHUP', 'SIGABRT'];
+	for (const signal of signals) {
+		process.on(signal, killed);
+	}
 
 	const head = [
 		`🐳 ${trigger} (New scraping)`,
 		...Object.entries(config).map(([key, value]) => `  ${key}: ${value}`),
 	];
-	return eventAssignments(orchestrator, head, logType);
+	try {
+		return await eventAssignments(orchestrator, head, logType);
+	} finally {
+		for (const signal of signals) {
+			process.removeListener(signal, killed);
+		}
+	}
 }
 
 /**
diff --git a/packages/@nitpicker/report-google-sheets/src/archive.spec.ts b/packages/@nitpicker/report-google-sheets/src/archive.spec.ts
new file mode 100644
index 0000000..b95085b
--- /dev/null
+++ b/packages/@nitpicker/report-google-sheets/src/archive.spec.ts
@@ -0,0 +1,71 @@
+import { afterEach, beforeEach, describe, it, expect, vi } from 'vitest';
+
+const mockOpen = vi.fn();
+const mockClose = vi.fn();
+
+vi.mock('@nitpicker/crawler', () => ({
+	Archive: {
+		open: mockOpen,
+	},
+}));
+
+vi.mock('./debug.js', () => ({
+	archiveLog: vi.fn(),
+}));
+
+describe('getArchive', () => {
+	beforeEach(() => {
+		vi.clearAllMocks();
+		mockOpen.mockResolvedValue({ close: mockClose });
+	});
+
+	afterEach(() => {
+		vi.restoreAllMocks();
+	});
+
+	it('archive と removeSignalHandlers を含むオブジェクトを返す', async () => {
+		const { getArchive } = await import('./archive.js');
+		const handle = await getArchive('/tmp/test.nitpicker');
+
+		expect(handle).toHaveProperty('archive');
+		expect(handle).toHaveProperty('removeSignalHandlers');
+		expect(typeof handle.removeSignalHandlers).toBe('function');
+	});
+
+	it('シグナルリスナーを登録する', async () => {
+		const { getArchive } = await import('./archive.js');
+		const before = process.listenerCount('SIGINT');
+
+		await getArchive('/tmp/test.nitpicker');
+
+		expect(process.listenerCount('SIGINT')).toBe(before + 1);
+		expect(process.listenerCount('SIGHUP')).toBeGreaterThan(0);
+		expect(process.listenerCount('SIGABRT')).toBeGreaterThan(0);
+	});
+
+	it('removeSignalHandlers を呼ぶとシグナルリスナーが解除される', async () => {
+		const { getArchive } = await import('./archive.js');
+		const before = process.listenerCount('SIGINT');
+
+		const { removeSignalHandlers } = await getArchive('/tmp/test.nitpicker');
+		removeSignalHandlers();
+
+		expect(process.listenerCount('SIGINT')).toBe(before);
+	});
+
+	it('複数回呼び出してもリスナーが蓄積しない（removeSignalHandlers で解除した場合）', async () => {
+		const { getArchive } = await import('./archive.js');
+		const before = process.listenerCount('SIGINT');
+
+		const handle1 = await getArchive('/tmp/test1.nitpicker');
+		handle1.removeSignalHandlers();
+
+		const handle2 = await getArchive('/tmp/test2.nitpicker');
+		handle2.removeSignalHandlers();
+
+		const handle3 = await getArchive('/tmp/test3.nitpicker');
+		handle3.removeSignalHandlers();
+
+		expect(process.listenerCount('SIGINT')).toBe(before);
+	});
+});
diff --git a/packages/@nitpicker/report-google-sheets/src/archive.ts b/packages/@nitpicker/report-google-sheets/src/archive.ts
index 3888a77..8e9bdc8 100644
--- a/packages/@nitpicker/report-google-sheets/src/archive.ts
+++ b/packages/@nitpicker/report-google-sheets/src/archive.ts
@@ -2,13 +2,26 @@ import { Archive } from '@nitpicker/crawler';
 
 import { archiveLog } from './debug.js';
 
+/**
+ * Result of opening an archive with signal handlers registered.
+ */
+export interface ArchiveHandle {
+	/** The opened archive instance. */
+	readonly archive: Archive;
+	/** Removes the registered signal handlers. Call this when the archive is no longer in use. */
+	readonly removeSignalHandlers: () => void;
+}
+
 /**
  * Opens a `.nitpicker` archive file and registers process signal handlers
  * to ensure the archive is closed gracefully on unexpected termination.
+ *
+ * The caller must invoke `removeSignalHandlers()` when the archive is no
+ * longer needed to avoid listener accumulation.
  * @param filePath - Path to the `.nitpicker` archive file
- * @returns The opened `Archive` instance with plugin data loaded
+ * @returns An {@link ArchiveHandle} containing the archive and a cleanup function.
  */
-export async function getArchive(filePath: string) {
+export async function getArchive(filePath: string): Promise<ArchiveHandle> {
 	archiveLog('Open file: %s', filePath);
 	const archive = await Archive.open({
 		filePath,
@@ -16,16 +29,23 @@ export async function getArchive(filePath: string) {
 	});
 	archiveLog('File open succeeded');
 
+	const signals: NodeJS.Signals[] = ['SIGINT', 'SIGBREAK', 'SIGHUP', 'SIGABRT'];
+
 	const close = async () => {
 		await archive.close();
 		process.exit();
 	};
 
 	archiveLog('Bind close method to SIGINT, SIGBREAK, SIGHUP, SIGABRT events');
-	process.on('SIGINT', close);
-	process.on('SIGBREAK', close);
-	process.on('SIGHUP', close);
-	process.on('SIGABRT', close);
+	for (const signal of signals) {
+		process.on(signal, close);
+	}
+
+	const removeSignalHandlers = () => {
+		for (const signal of signals) {
+			process.removeListener(signal, close);
+		}
+	};
 
-	return archive;
+	return { archive, removeSignalHandlers };
 }
diff --git a/packages/@nitpicker/report-google-sheets/src/report.spec.ts b/packages/@nitpicker/report-google-sheets/src/report.spec.ts
index f6e3740..1d0ef35 100644
--- a/packages/@nitpicker/report-google-sheets/src/report.spec.ts
+++ b/packages/@nitpicker/report-google-sheets/src/report.spec.ts
@@ -14,9 +14,15 @@ vi.mock('@d-zero/google-sheets', () => ({
 	},
 }));
 
+const { mockArchiveClose, mockRemoveSignalHandlers } = vi.hoisted(() => ({
+	mockArchiveClose: vi.fn(),
+	mockRemoveSignalHandlers: vi.fn(),
+}));
+
 vi.mock('./archive.js', () => ({
 	getArchive: vi.fn().mockResolvedValue({
-		close: vi.fn(),
+		archive: { close: mockArchiveClose },
+		removeSignalHandlers: mockRemoveSignalHandlers,
 	}),
 }));
 
@@ -87,6 +93,23 @@ describe('report', () => {
 		expect(lanesSpy).toHaveBeenCalled();
 	});
 
+	it('正常完了時に removeSignalHandlers と archive.close を呼び出す', async () => {
+		await report({ ...baseParams, all: true });
+
+		expect(mockRemoveSignalHandlers).toHaveBeenCalledTimes(1);
+		expect(mockArchiveClose).toHaveBeenCalledTimes(1);
+	});
+
+	it('createSheets が例外をスローしても removeSignalHandlers と archive.close を呼び出す', async () => {
+		const { createSheets } = await import('./sheets/create-sheets.js');
+		vi.mocked(createSheets).mockRejectedValueOnce(new Error('sheets error'));
+
+		await expect(report({ ...baseParams, all: true })).rejects.toThrow('sheets error');
+
+		expect(mockRemoveSignalHandlers).toHaveBeenCalledTimes(1);
+		expect(mockArchiveClose).toHaveBeenCalledTimes(1);
+	});
+
 	it('passes all 9 sheets to createSheets when all=true', async () => {
 		const { createSheets } = await import('./sheets/create-sheets.js');
 
diff --git a/packages/@nitpicker/report-google-sheets/src/report.ts b/packages/@nitpicker/report-google-sheets/src/report.ts
index f52d81f..3b9bf2c 100644
--- a/packages/@nitpicker/report-google-sheets/src/report.ts
+++ b/packages/@nitpicker/report-google-sheets/src/report.ts
@@ -83,171 +83,172 @@ export async function report(params: ReportParams) {
 	log('Authentication succeeded');
 
 	log('Opening archive: %s', filePath);
-	const archive = await getArchive(filePath);
+	const { archive, removeSignalHandlers } = await getArchive(filePath);
 	log('Archive opened');
 
-	log('Loading config');
-	const config = await loadConfig(configPath);
-	log('Config loaded');
-
-	const plugins = config.plugins?.analyze
-		? Object.keys(config.plugins.analyze)
-		: undefined;
-	log('Loaded plugins: %O', plugins);
-
-	log('Loading plugin reports');
-	const reports = await getPluginReports(archive /*plugins*/);
-	log('Plugin reports loaded: %d', reports.length);
-
-	const sheets = new Sheets(sheetUrl, auth);
-
-	log('Reporting starts');
-
-	const sheetNames = [
-		'Page List' as const,
-		'Links' as const,
-		'Resources' as const,
-		'Images' as const,
-		'Violations' as const,
-		'Discrepancies' as const,
-		'Summary' as const,
-		'Referrers Relational Table' as const,
-		'Resources Relational Table' as const,
-	];
-	type SheetNames = typeof sheetNames;
-
-	let selectedSheetNames: SheetNames;
-
-	if (all) {
-		log('All sheets selected (--all or non-TTY)');
-		selectedSheetNames = sheetNames;
-	} else {
-		log('Choice creating data');
-		const chosenSheets = await enquirer
-			.prompt<{ sheetName: SheetNames }>([
-				{
-					message: 'What do you report?',
-					name: 'sheetName',
-					type: 'multiselect',
-					choices: sheetNames,
-				},
-			])
-			.catch(() => {
-				// enquirer v2.4.1: Ctrl+C 後に readline を二重 close して
-				// ERR_USE_AFTER_CLOSE が unhandled rejection になるため、
-				// 即座に終了して回避する
-				process.exit(0);
-			});
-
-		if (!chosenSheets) {
+	try {
+		log('Loading config');
+		const config = await loadConfig(configPath);
+		log('Config loaded');
+
+		const plugins = config.plugins?.analyze
+			? Object.keys(config.plugins.analyze)
+			: undefined;
+		log('Loaded plugins: %O', plugins);
+
+		log('Loading plugin reports');
+		const reports = await getPluginReports(archive /*plugins*/);
+		log('Plugin reports loaded: %d', reports.length);
+
+		const sheets = new Sheets(sheetUrl, auth);
+
+		log('Reporting starts');
+
+		const sheetNames = [
+			'Page List' as const,
+			'Links' as const,
+			'Resources' as const,
+			'Images' as const,
+			'Violations' as const,
+			'Discrepancies' as const,
+			'Summary' as const,
+			'Referrers Relational Table' as const,
+			'Resources Relational Table' as const,
+		];
+		type SheetNames = typeof sheetNames;
+
+		let selectedSheetNames: SheetNames;
+
+		if (all) {
+			log('All sheets selected (--all or non-TTY)');
+			selectedSheetNames = sheetNames;
+		} else {
 			log('Choice creating data');
-			archiveLog('Closes file');
-			await archive.close();
-			return;
-		}
+			const chosenSheets = await enquirer
+				.prompt<{ sheetName: SheetNames }>([
+					{
+						message: 'What do you report?',
+						name: 'sheetName',
+						type: 'multiselect',
+						choices: sheetNames,
+					},
+				])
+				.catch(() => {
+					// enquirer v2.4.1: Ctrl+C 後に readline を二重 close して
+					// ERR_USE_AFTER_CLOSE が unhandled rejection になるため、
+					// 即座に終了して回避する
+					process.exit(0);
+				});
+
+			if (!chosenSheets) {
+				log('Choice creating data');
+				return;
+			}
 
-		selectedSheetNames = chosenSheets.sheetName;
-	}
+			selectedSheetNames = chosenSheets.sheetName;
+		}
 
-	log('Chosen sheets: %O', selectedSheetNames);
+		log('Chosen sheets: %O', selectedSheetNames);
 
-	const createSheetList: CreateSheet[] = [];
+		const createSheetList: CreateSheet[] = [];
 
-	if (selectedSheetNames.includes('Page List')) {
-		createSheetList.push(createPageList);
-	}
+		if (selectedSheetNames.includes('Page List')) {
+			createSheetList.push(createPageList);
+		}
 
-	if (selectedSheetNames.includes('Links')) {
-		createSheetList.push(createLinks);
-	}
+		if (selectedSheetNames.includes('Links')) {
+			createSheetList.push(createLinks);
+		}
 
-	if (selectedSheetNames.includes('Discrepancies')) {
-		createSheetList.push(createDiscrepancies);
-	}
+		if (selectedSheetNames.includes('Discrepancies')) {
+			createSheetList.push(createDiscrepancies);
+		}
 
-	if (selectedSheetNames.includes('Violations')) {
-		createSheetList.push(createViolations);
-	}
+		if (selectedSheetNames.includes('Violations')) {
+			createSheetList.push(createViolations);
+		}
 
-	if (selectedSheetNames.includes('Referrers Relational Table')) {
-		createSheetList.push(createReferrersRelationalTable);
-	}
+		if (selectedSheetNames.includes('Referrers Relational Table')) {
+			createSheetList.push(createReferrersRelationalTable);
+		}
 
-	if (selectedSheetNames.includes('Resources Relational Table')) {
-		createSheetList.push(createResourcesRelationalTable);
-	}
+		if (selectedSheetNames.includes('Resources Relational Table')) {
+			createSheetList.push(createResourcesRelationalTable);
+		}
 
-	if (selectedSheetNames.includes('Resources')) {
-		createSheetList.push(createResources);
-	}
+		if (selectedSheetNames.includes('Resources')) {
+			createSheetList.push(createResources);
+		}
 
-	if (selectedSheetNames.includes('Images')) {
-		createSheetList.push(createImageList);
-	}
+		if (selectedSheetNames.includes('Images')) {
+			createSheetList.push(createImageList);
+		}
 
-	if (!silent) {
-		// eslint-disable-next-line no-console
-		console.log(`\nGenerating ${createSheetList.length} sheet(s)...\n`);
-	}
+		if (!silent) {
+			// eslint-disable-next-line no-console
+			console.log(`\nGenerating ${createSheetList.length} sheet(s)...\n`);
+		}
 
-	const lanes = silent
-		? null
-		: new Lanes({ verbose: !process.stdout.isTTY, indent: '  ' });
-	log('Lanes created (verbose: %s, silent: %s)', !process.stdout.isTTY, !!silent);
-
-	const RATE_LIMIT_LANE = 10_000;
-	let countdownSeq = 0;
-	let waitingCount = 0;
-
-	if (lanes) {
-		sheets.onLog = (message: ErrorHandlerMessage) => {
-			if (message.waiting && message.waitTime) {
-				waitingCount++;
-				const id = `rateLimit_${countdownSeq++}`;
-				const label =
-					message.message === 'TooManyRequestError'
-						? 'Too Many Requests (429)'
-						: message.message === 'UserRateLimitExceededError'
-							? 'Rate Limit Exceeded (403)'
-							: 'Connection Reset';
-				lanes.update(
-					RATE_LIMIT_LANE,
-					c.yellow(`${label}: waiting %countdown(${message.waitTime}, ${id}, s)%s`),
-				);
-			} else {
-				waitingCount--;
-				if (waitingCount <= 0) {
-					waitingCount = 0;
-					lanes.delete(RATE_LIMIT_LANE);
+		const lanes = silent
+			? null
+			: new Lanes({ verbose: !process.stdout.isTTY, indent: '  ' });
+		log('Lanes created (verbose: %s, silent: %s)', !process.stdout.isTTY, !!silent);
+
+		const RATE_LIMIT_LANE = 10_000;
+		let countdownSeq = 0;
+		let waitingCount = 0;
+
+		if (lanes) {
+			sheets.onLog = (message: ErrorHandlerMessage) => {
+				if (message.waiting && message.waitTime) {
+					waitingCount++;
+					const id = `rateLimit_${countdownSeq++}`;
+					const label =
+						message.message === 'TooManyRequestError'
+							? 'Too Many Requests (429)'
+							: message.message === 'UserRateLimitExceededError'
+								? 'Rate Limit Exceeded (403)'
+								: 'Connection Reset';
+					lanes.update(
+						RATE_LIMIT_LANE,
+						c.yellow(`${label}: waiting %countdown(${message.waitTime}, ${id}, s)%s`),
+					);
+				} else {
+					waitingCount--;
+					if (waitingCount <= 0) {
+						waitingCount = 0;
+						lanes.delete(RATE_LIMIT_LANE);
+					}
 				}
-			}
-		};
-	}
+			};
+		}
 
-	log('Reporting starts (limit: %d)', limit);
-	try {
-		await createSheets({
-			sheets,
-			archive,
-			reports,
-			limit,
-			createSheetList,
-			options: lanes ? { lanes } : undefined,
-		});
-	} finally {
-		lanes?.close();
-	}
-	log('Reporting done');
-	if (!silent) {
-		// eslint-disable-next-line no-console
-		console.log('\nReport complete.');
-	}
+		log('Reporting starts (limit: %d)', limit);
+		try {
+			await createSheets({
+				sheets,
+				archive,
+				reports,
+				limit,
+				createSheetList,
+				options: lanes ? { lanes } : undefined,
+			});
+		} finally {
+			lanes?.close();
+		}
+		log('Reporting done');
+		if (!silent) {
+			// eslint-disable-next-line no-console
+			console.log('\nReport complete.');
+		}
 
-	if (selectedSheetNames.includes('Summary')) {
-		await addToSummary(/*sheets, archive, reports*/);
+		if (selectedSheetNames.includes('Summary')) {
+			await addToSummary(/*sheets, archive, reports*/);
+		}
+	} finally {
+		archiveLog('Closes file');
+		removeSignalHandlers();
+		await archive.close();
+		log('Done');
 	}
-
-	archiveLog('Closes file');
-	await archive.close();
-	log('Done');
 }