In order to realize the security authentication of information transmission between vehicle nodes in the vehicular ad hoc network, based on the certificateless public key cryptosystem and aggregate signature, a privacy-protected certificateless aggregate signature scheme is proposed, which eliminates the complicated certificate maintenance cost. This solution also solves the key escrow problem. By Communicating with surrounding nodes through the pseudonym of the vehicle, the privacy protection of vehicle users is realized. The signature scheme satisfies the unforgeability of an adaptive selective message attack under a random prophetic machine. The scheme meets message authentication, identity privacy protection, resistance to reply attacks.