Remote attestation is an important attribute in trusted computing. One of the purpose of remote attestation is to attest the remote platform is trusty but not revealing the actual identity of the platform. Direct anonymous attestation (DAA) is a kind of scheme which is adopted by Trusted Computing Group in the specification 1.2 to hide the privacy of the platform. But DAA involves various of zero-knowledge proofs and is not efficient to implement. To guarantee the trustworthiness and privacy, we propose a remote anonymous attestation protocol based on ring signature in this paper. We also show that our protocol is secure under the RSA assumption in random oracle model. Furthermore, the attestation protocol does not need the third party and extra zero-knowledge proof, which makes it very efficient in realization.