Abstract: The security of a certificateless partially blind signature scheme put forward by He Junjie et al was analyzed, it was found that there was a common information tampered illegally by a user problem. In order to ensure that common information is not tampered, an improved certificateless partially blind signature scheme based on the collusion attack algorithm with k-traitors (k-CAA) and inverse computational Diffie-Hellman (ICDH) problem was proposed, and then  its correctness, partially blind and security were analyzed. The new scheme was proved to be existentially unforgeable for the adaptive chosen message and the attacks from two kinds of adversaries in random oracle model