diff --git a/cdk/src/lambda/handlers/passwordReset.ts b/cdk/src/lambda/handlers/passwordReset.ts
index 39b0680..fe8728a 100644
--- a/cdk/src/lambda/handlers/passwordReset.ts
+++ b/cdk/src/lambda/handlers/passwordReset.ts
@@ -2,6 +2,7 @@ import { APIGatewayProxyHandler } from 'aws-lambda';
 import { doesUserExistByEmail, resetUserPassword } from '../../service/cognito';
 import { successResponse, errorResponse, wrapHandler } from '../handlerUtil';
 import { getEmailVerifiedToken, deleteEmailVerifiedToken } from '../../service/email/emailVerifiedToken';
+import { CustomPasswordError, checkPasswordPolicy } from '../../service/passwordPolicy';
 
 const passwordReset: APIGatewayProxyHandler = async event => {
   const email = event.queryStringParameters?.email;
@@ -32,13 +33,18 @@ const passwordReset: APIGatewayProxyHandler = async event => {
       return errorResponse('New password is required', 400);
     }
 
+    await checkPasswordPolicy(newPassword);
+
     // Reset the user password and remove the email verified token after successful password reset
     await resetUserPassword(email, newPassword);
     await deleteEmailVerifiedToken(email);
 
     return successResponse({ message: 'Password reset successfully' });
   } catch (error) {
-    return errorResponse(error instanceof Error ? error.message : 'Password reset failed', 500);
+    if (error instanceof CustomPasswordError) {
+      return errorResponse(error.message, 400);
+    }
+    return errorResponse('Password reset failed', 500);
   }
 };
 
diff --git a/cdk/src/lambda/handlers/userRegistration.ts b/cdk/src/lambda/handlers/userRegistration.ts
index 86df2f6..939a92c 100644
--- a/cdk/src/lambda/handlers/userRegistration.ts
+++ b/cdk/src/lambda/handlers/userRegistration.ts
@@ -2,6 +2,7 @@ import { APIGatewayProxyHandler } from 'aws-lambda';
 import { successResponse, errorResponse, wrapHandler } from '../handlerUtil';
 import { getEmailVerifiedToken, deleteEmailVerifiedToken } from '../../service/email/emailVerifiedToken';
 import { createUserInCognito } from '../../service/cognito';
+import { CustomPasswordError, checkPasswordPolicy } from '../../service/passwordPolicy';
 
 export const handler: APIGatewayProxyHandler = wrapHandler(async event => {
   const emailVerifiedToken = event.queryStringParameters?.emailVerifiedToken;
@@ -28,6 +29,14 @@ export const handler: APIGatewayProxyHandler = wrapHandler(async event => {
     return errorResponse('Invalid email verified token', 401);
   }
 
+  try {
+    await checkPasswordPolicy(password);
+  } catch (error) {
+    if (error instanceof CustomPasswordError) {
+      return errorResponse(error.message, 400);
+    }
+  }
+
   // Proceed with user registration in Cognito
   const { AccessToken, IdToken, RefreshToken } = await createUserInCognito(email, password);
 
diff --git a/cdk/src/service/passwordPolicy.ts b/cdk/src/service/passwordPolicy.ts
new file mode 100644
index 0000000..c0273f4
--- /dev/null
+++ b/cdk/src/service/passwordPolicy.ts
@@ -0,0 +1,32 @@
+export class CustomPasswordError extends Error {
+  constructor(message: string) {
+    super(message);
+    this.name = 'CustomPasswordError';
+  }
+}
+
+export async function checkPasswordPolicy(password: string): Promise<void> {
+  if (password.length < 8) {
+    throw new CustomPasswordError('Password must be at least 8 characters');
+  }
+
+  if (password.length > 20) {
+    throw new CustomPasswordError('Password cannot exceed 20 characters');
+  }
+
+  if (!/[A-Z]/.test(password)) {
+    throw new CustomPasswordError('Password must contain at least one uppercase letter');
+  }
+
+  if (!/[a-z]/.test(password)) {
+    throw new CustomPasswordError('Password must contain at least one lowercase letter');
+  }
+
+  if (!/[!@#$%^&*(),.?":{}|<>]/.test(password)) {
+    throw new CustomPasswordError('Password must contain at least one special character');
+  }
+
+  if (!/[0-9]/.test(password)) {
+    throw new CustomPasswordError('Password must contain at least one number');
+  }
+}
diff --git a/cdk/test/lambda/handlers/passwordReset.test.ts b/cdk/test/lambda/handlers/passwordReset.test.ts
index c994cae..b93b3cc 100644
--- a/cdk/test/lambda/handlers/passwordReset.test.ts
+++ b/cdk/test/lambda/handlers/passwordReset.test.ts
@@ -10,7 +10,8 @@ jest.mock('../../../src/service/email/emailVerifiedToken');
 describe('passwordReset', () => {
   const mockStoredEmailVerifiedToken = 'stored-email-verified-token';
   const mockEmail = 'test@sfu.ca';
-  const mockNewPassword = 'newPassword123';
+  const mockNewPassword = 'newPassword@!#123';
+  const mockInvalidPassword = 'newPassword';
 
   const invokeHandler = async (event: Partial<APIGatewayProxyEvent>) => {
     const context = {} as Context;
@@ -67,6 +68,16 @@ describe('passwordReset', () => {
     expect(handlerUtil.errorResponse).toHaveBeenCalledWith('New password is required', 400);
   });
 
+  it('should call errorResponse when password is shorter than 8 characters', async () => {
+    await invokeHandler({
+      queryStringParameters: { email: mockEmail, emailVerifiedToken: mockStoredEmailVerifiedToken },
+      body: JSON.stringify({ newPassword: mockInvalidPassword }),
+    });
+    expect(handlerUtil.errorResponse).toHaveBeenCalledWith(expect.stringMatching(/Password/), 400);
+    expect(resetUserPassword).not.toHaveBeenCalled();
+    expect(deleteEmailVerifiedToken).not.toHaveBeenCalled();
+  });
+
   it('should reset password successfully with valid inputs', async () => {
     await invokeHandler({
       queryStringParameters: { email: mockEmail, emailVerifiedToken: mockStoredEmailVerifiedToken },