The invention discloses a user identification authentication method, related equipment and a system in wireless application protocol business for improving the validity of user identification authentication and the safety of user information in WAP business; wherein the method comprises: a mobile information management platform receives the user identifier information sent by a wireless application protocol network element; wherein the user identifier information is obtained by encrypting the user identifier information of the user initiating wireless application protocol business request by the network element; the network element decrypts the received user identifier information based on the encryption information and authenticates whether the user is a legal user of the wireless application protocol business based on the decrypted user identifier information.