To tackle the problems of security threat and the shortcomings in the process of ID authentication between user and cloud, this paper applies Portable TPM chip and certificateless public key cryptography for the first time to solve the issues in the cloud environment, and proposes a scheme for bidirectional ID authentication between user and cloud. Compared with previous authentication schemes, the proposed scheme has the several advantages. First, based on the unique identity of user and cloud by the identity management mechanism, portable TPM can not only achieves secure and trusted terminal platform, which ensures the authentication result between user and cloud is correct and valid, but also supports the objectives of ID authentication between user and cloud in user's any terminal device. Furthermore, Dual-factor ID authentication (password + key) is implemented with certificateless public key signature algorithm provided by the new scheme. Finally, security proof and performance analysis show that this proposed scheme has the security level of EUF-CMA, and the computation overhead of ID authentication between user and cloud is significantly improved.