Certificateless public key cryptography reduces the difficult problem of key management in traditional public key cryptography, it also eliminates the key-escrow problem of identity-based cryptography and also preserves all of its advantages. A the lowest calculating time forward secure ring signature scheme is proposed, it can resist forgery attacks from the secret key generation center and can meet with the requirements of unconditional anonymity of signers, it can resist forgery attacks as the secret keys of signer is revealed, so it is suitable to the application of high security and anonymity.