Abstract: Based on the basic theories of RSA signature, GQ signature, and IR forward secure signature, a group signature scheme with forward security is presented. In this signature scheme, the key server only generates one public key for all members of group and all members share this public key. At the same time, the key server also generates the secret key “seeds” for each member, thus, each member can only get one secret key “seed”. During each time period, each member of group can generate or update his own secret key by using the secret key generation algorithm or the secret key update algorithm. By analyzing the performance of the digital signature, a conclusion may be drawn. It can be described as follows: In a group communication that includes n members, if the digital signature is adopted, and even (n-1) members corrupt, the only one legal member is still secure under such attacks.