As an important component of Intelligent Transportation Systems (ITS), vehicular ad hoc networks can provide safer and more comfortable driving circumstance for the drivers. Pseudonyms certificate and group-oriented signature are two most widely adopted privacy- preserving technique in VANET. However, the two methods exists many efficiency flaws which affect their application. To overcome the above problems which exist in the above two methods. In this paper, we propose a novel privacy-preserving authentication protocols based on self-certified signature. And we show that our scheme can achieve conditional privacy-preserving and is proven be secure in the random oracle. Furthermore, the scheme has the following advantages: short length of the signature and low computation.