diff --git a/packages/core/src/config/storage.ts b/packages/core/src/config/storage.ts
index 8ef0283c509..f9d0107e55a 100644
--- a/packages/core/src/config/storage.ts
+++ b/packages/core/src/config/storage.ts
@@ -6,8 +6,8 @@
 
 import * as path from 'node:path';
 import * as os from 'node:os';
-import * as crypto from 'node:crypto';
 import * as fs from 'node:fs';
+import { getProjectHash } from '../utils/paths.js';
 
 export const QWEN_DIR = '.qwen';
 export const GOOGLE_ACCOUNTS_FILENAME = 'google_accounts.json';
@@ -88,9 +88,10 @@ export class Storage {
   }
 
   getProjectTempDir(): string {
-    const hash = this.getFilePathHash(this.getProjectRoot());
+    const hash = getProjectHash(this.getProjectRoot());
     const tempDir = Storage.getGlobalTempDir();
-    return path.join(tempDir, hash);
+    const targetDir = path.join(tempDir, hash);
+    return targetDir;
   }
 
   ensureProjectTempDirExists(): void {
@@ -105,14 +106,11 @@ export class Storage {
     return this.targetDir;
   }
 
-  private getFilePathHash(filePath: string): string {
-    return crypto.createHash('sha256').update(filePath).digest('hex');
-  }
-
   getHistoryDir(): string {
-    const hash = this.getFilePathHash(this.getProjectRoot());
+    const hash = getProjectHash(this.getProjectRoot());
     const historyDir = path.join(Storage.getGlobalQwenDir(), 'history');
-    return path.join(historyDir, hash);
+    const targetDir = path.join(historyDir, hash);
+    return targetDir;
   }
 
   getWorkspaceSettingsPath(): string {
@@ -144,6 +142,8 @@ export class Storage {
   }
 
   private sanitizeCwd(cwd: string): string {
-    return cwd.replace(/[^a-zA-Z0-9]/g, '-');
+    // On Windows, normalize to lowercase for case-insensitive matching
+    const normalizedCwd = os.platform() === 'win32' ? cwd.toLowerCase() : cwd;
+    return normalizedCwd.replace(/[^a-zA-Z0-9]/g, '-');
   }
 }
diff --git a/packages/core/src/core/logger.test.ts b/packages/core/src/core/logger.test.ts
index de3fc3f787c..c973c02dd3b 100644
--- a/packages/core/src/core/logger.test.ts
+++ b/packages/core/src/core/logger.test.ts
@@ -21,11 +21,11 @@ import {
   decodeTagName,
 } from './logger.js';
 import { Storage } from '../config/storage.js';
+import { getProjectHash } from '../utils/paths.js';
 import { promises as fs, existsSync } from 'node:fs';
 import path from 'node:path';
 import type { Content } from '@google/genai';
 
-import crypto from 'node:crypto';
 import os from 'node:os';
 
 const GEMINI_DIR_NAME = '.qwen';
@@ -34,7 +34,7 @@ const LOG_FILE_NAME = 'logs.json';
 const CHECKPOINT_FILE_NAME = 'checkpoint.json';
 
 const projectDir = process.cwd();
-const hash = crypto.createHash('sha256').update(projectDir).digest('hex');
+const hash = getProjectHash(projectDir);
 const TEST_HOME_DIR = path.join(os.tmpdir(), 'qwen-core-logger-home');
 
 let originalHome: string | undefined;
diff --git a/packages/core/src/utils/paths.test.ts b/packages/core/src/utils/paths.test.ts
index 1c4ee0225f5..9f8b63ef97b 100644
--- a/packages/core/src/utils/paths.test.ts
+++ b/packages/core/src/utils/paths.test.ts
@@ -17,6 +17,7 @@ import {
   isSubpath,
   shortenPath,
   tildeifyPath,
+  getProjectHash,
 } from './paths.js';
 import type { Config } from '../config/config.js';
 
@@ -770,3 +771,80 @@ describe('shortenPath', () => {
     expect(result.length).toBeLessThanOrEqual(35);
   });
 });
+
+describe('getProjectHash', () => {
+  it('should generate consistent hashes for the same path', () => {
+    const projectRoot = '/test/project';
+    const hash1 = getProjectHash(projectRoot);
+    const hash2 = getProjectHash(projectRoot);
+
+    expect(hash1).toBe(hash2);
+    expect(hash1).toHaveLength(64); // SHA256 produces 64 hex characters
+  });
+
+  it('should generate different hashes for different paths', () => {
+    const hash1 = getProjectHash('/test/project1');
+    const hash2 = getProjectHash('/test/project2');
+
+    expect(hash1).not.toBe(hash2);
+  });
+
+  it('should generate case-insensitive hashes on Windows', () => {
+    const platformSpy = vi.spyOn(os, 'platform');
+
+    // Simulate Windows platform
+    platformSpy.mockReturnValue('win32');
+
+    const lowerCasePath = 'c:\\users\\test\\project';
+    const upperCasePath = 'C:\\Users\\Test\\Project';
+    const mixedCasePath = 'c:\\Users\\TEST\\project';
+
+    const hash1 = getProjectHash(lowerCasePath);
+    const hash2 = getProjectHash(upperCasePath);
+    const hash3 = getProjectHash(mixedCasePath);
+
+    // On Windows, all different case variations should produce the same hash
+    expect(hash1).toBe(hash2);
+    expect(hash2).toBe(hash3);
+
+    platformSpy.mockRestore();
+  });
+
+  it('should generate case-sensitive hashes on non-Windows platforms', () => {
+    const platformSpy = vi.spyOn(os, 'platform');
+
+    // Simulate Unix/Linux platform
+    platformSpy.mockReturnValue('linux');
+
+    const lowerCasePath = '/home/user/project';
+    const upperCasePath = '/HOME/USER/PROJECT';
+
+    const hash1 = getProjectHash(lowerCasePath);
+    const hash2 = getProjectHash(upperCasePath);
+
+    // On non-Windows platforms, different case should produce different hashes
+    expect(hash1).not.toBe(hash2);
+
+    platformSpy.mockRestore();
+  });
+
+  it('should handle Windows drive letter variations', () => {
+    const platformSpy = vi.spyOn(os, 'platform');
+    platformSpy.mockReturnValue('win32');
+
+    // Common Windows scenarios where users might have different drive letter cases
+    const scenarios = [
+      ['e:\\work', 'E:\\work'],
+      ['e:\\work', 'E:\\WORK'],
+      ['c:\\projects\\myapp', 'C:\\Projects\\MyApp'],
+    ];
+
+    for (const [path1, path2] of scenarios) {
+      const hash1 = getProjectHash(path1);
+      const hash2 = getProjectHash(path2);
+      expect(hash1).toBe(hash2);
+    }
+
+    platformSpy.mockRestore();
+  });
+});
diff --git a/packages/core/src/utils/paths.ts b/packages/core/src/utils/paths.ts
index 6b492c92291..96856a5dcc6 100644
--- a/packages/core/src/utils/paths.ts
+++ b/packages/core/src/utils/paths.ts
@@ -190,11 +190,16 @@ export function unescapePath(filePath: string): string {
 
 /**
  * Generates a unique hash for a project based on its root path.
+ * On Windows, paths are case-insensitive, so we normalize to lowercase
+ * to ensure the same physical path always produces the same hash.
  * @param projectRoot The absolute path to the project's root directory.
  * @returns A SHA256 hash of the project root path.
  */
 export function getProjectHash(projectRoot: string): string {
-  return crypto.createHash('sha256').update(projectRoot).digest('hex');
+  // On Windows, normalize path to lowercase for case-insensitive matching
+  const normalizedPath =
+    os.platform() === 'win32' ? projectRoot.toLowerCase() : projectRoot;
+  return crypto.createHash('sha256').update(normalizedPath).digest('hex');
 }
 
 /**
diff --git a/packages/vscode-ide-companion/src/services/qwenSessionManager.ts b/packages/vscode-ide-companion/src/services/qwenSessionManager.ts
index 9336a060bfd..a5e817cad42 100644
--- a/packages/vscode-ide-companion/src/services/qwenSessionManager.ts
+++ b/packages/vscode-ide-companion/src/services/qwenSessionManager.ts
@@ -8,6 +8,7 @@ import * as fs from 'fs';
 import * as path from 'path';
 import * as os from 'os';
 import * as crypto from 'crypto';
+import { getProjectHash } from '@qwen-code/qwen-code-core/src/utils/paths.js';
 import type { QwenSession, QwenMessage } from './qwenSessionReader.js';
 
 /**
@@ -28,19 +29,12 @@ export class QwenSessionManager {
   }
 
   /**
-   * Calculate project hash (same as CLI)
-   * Qwen CLI uses SHA256 hash of the project path
-   */
-  private getProjectHash(workingDir: string): string {
-    return crypto.createHash('sha256').update(workingDir).digest('hex');
-  }
-
-  /**
-   * Get the session directory for a project
+   * Get the session directory for a project with backward compatibility
    */
   private getSessionDir(workingDir: string): string {
-    const projectHash = this.getProjectHash(workingDir);
-    return path.join(this.qwenDir, 'tmp', projectHash, 'chats');
+    const projectHash = getProjectHash(workingDir);
+    const sessionDir = path.join(this.qwenDir, 'tmp', projectHash, 'chats');
+    return sessionDir;
   }
 
   /**
@@ -87,7 +81,7 @@ export class QwenSessionManager {
       // Create session object
       const session: QwenSession = {
         sessionId,
-        projectHash: this.getProjectHash(workingDir),
+        projectHash: getProjectHash(workingDir),
         startTime: messages[0]?.timestamp || new Date().toISOString(),
         lastUpdated: new Date().toISOString(),
         messages,
diff --git a/packages/vscode-ide-companion/src/services/qwenSessionReader.ts b/packages/vscode-ide-companion/src/services/qwenSessionReader.ts
index 3fc4e484f23..0a65b0cb69d 100644
--- a/packages/vscode-ide-companion/src/services/qwenSessionReader.ts
+++ b/packages/vscode-ide-companion/src/services/qwenSessionReader.ts
@@ -8,7 +8,7 @@ import * as fs from 'fs';
 import * as path from 'path';
 import * as os from 'os';
 import * as readline from 'readline';
-import * as crypto from 'crypto';
+import { getProjectHash } from '@qwen-code/qwen-code-core/src/utils/paths.js';
 
 export interface QwenMessage {
   id: string;
@@ -58,7 +58,7 @@ export class QwenSessionReader {
 
       if (!allProjects && workingDir) {
         // Current project only
-        const projectHash = await this.getProjectHash(workingDir);
+        const projectHash = getProjectHash(workingDir);
         const chatsDir = path.join(this.qwenDir, 'tmp', projectHash, 'chats');
         const projectSessions = await this.readSessionsFromDir(chatsDir);
         sessions.push(...projectSessions);
@@ -177,14 +177,6 @@ export class QwenSessionReader {
     return found;
   }
 
-  /**
-   * Calculate project hash (needs to be consistent with Qwen CLI)
-   * Qwen CLI uses SHA256 hash of project path
-   */
-  private async getProjectHash(workingDir: string): Promise<string> {
-    return crypto.createHash('sha256').update(workingDir).digest('hex');
-  }
-
   /**
    * Get session title (based on first user message)
    */
@@ -289,7 +281,7 @@ export class QwenSessionReader {
       }
 
       const projectHash = cwd
-        ? await this.getProjectHash(cwd)
+        ? getProjectHash(cwd)
         : path.basename(path.dirname(path.dirname(filePath)));
 
       return {
diff --git a/scripts/telemetry_utils.js b/scripts/telemetry_utils.js
index cb2010d5b69..504ed18cb8c 100644
--- a/scripts/telemetry_utils.js
+++ b/scripts/telemetry_utils.js
@@ -18,10 +18,21 @@ const __filename = fileURLToPath(import.meta.url);
 const __dirname = path.dirname(__filename);
 
 const projectRoot = path.resolve(__dirname, '..');
-const projectHash = crypto
-  .createHash('sha256')
-  .update(projectRoot)
-  .digest('hex');
+
+/**
+ * Generates a unique hash for a project based on its root path.
+ * On Windows, paths are case-insensitive, so we normalize to lowercase
+ * to ensure the same physical path always produces the same hash.
+ * This logic must match getProjectHash() in packages/core/src/utils/paths.ts
+ */
+function getProjectHash(projectRoot) {
+  // On Windows, normalize path to lowercase for case-insensitive matching
+  const normalizedPath =
+    os.platform() === 'win32' ? projectRoot.toLowerCase() : projectRoot;
+  return crypto.createHash('sha256').update(normalizedPath).digest('hex');
+}
+
+const projectHash = getProjectHash(projectRoot);
 
 // User-level .gemini directory in home
 const USER_GEMINI_DIR = path.join(os.homedir(), '.qwen');