Abstract: A secure anonymous authentication scheme was proposed based on elliptic curve and zero-knowledge proof, which adopts a bidirectional anonymous authentication algorithm to preserve users’ privacy during the certification process. In the case of a high density traffic scenario, a message aggregation technology was proposed to realize fast authentication by the assistant of RSU, and to avoid the loss of massive messages unauthenticated promptly. The simulation and analytical results show that the proposed scheme yields a much better performance than previously reported counterparts with lower communication overhead, message loss rate and message delay.