Abstract: To solve the security problems in existing of the supersingular isogeny-based authentication key exchange protocol proposed by Galbraith, this paper proposes a new two-round authentication key exchange protocol based on CSIDH by using NAXOS techniques, and adding the Diffie-Hellman value of the static key of the two communicating parties to the calculation of the session key. Its proof of security was given. This protocol was currently the first authentication key exchange protocol based on the CSICDH problem assumption and provably secure under the eCK model. By comparison, the protocol has stronger safety attribute, which is specifically manifested in the ability to resist maximum exposure attacks and adaptive attacks.