Based on Chinese remainder theorem, this paper proposes an improved group signature scheme.The scheme combines with two different ElGamal signature schemes to strengthen authentication of the parameters between group members and group center and to generated final signature. The analysis of security shows that the improved scheme has the properties of anonymity, revocability, unlinkability and unforgeablity. In addition, the improved scheme can reduce the computational cost of signature scheme, improve the security of the signature scheme and the calculation efficiency.
