Deleting group members safely and efficiently has been a hot research issue in the field of the group signature. Some resolutions have been proposed by cryptography experts, but in some way, problems like loophole and low efficiency have been confusing us in the research. To solve the problem, the writers try to give a new secret key updating algorithm based on improving Wang Shangping’s group members deleting scheme, and analyze the safety and efficiency of implemen- tation systematically in the paper.