Method and apparatus for user authentication

A method and apparatus for authenticating a user is provided, the method includes: receiving an authentication request sent from a user device by a user; providing basic information in response to the authentication request, wherein the basic information comprises information related to a social networking service used by the user; generating authentication information based on the basic information, wherein the authentication information comprises a question and a corresponding answer; sending the question to the user device and receiving feedback information from the user device; and generating an authentication result by verifying whether the feedback information is consistent with the answer, and sending the authentication result to the user device. The method and apparatus address the issue of forgotten answers to security questions used in user authentication.