In this paper,we propose an enhanced attribute-based authenticated key agreement(ABAKA)protocol in the standard model.We construct our protocol based on Waters' ciphertextpolicy attribute-based encryption with a simple and compact conversion technique to the chosenplaintext attack(CPA)security from the chosen-ciphertext attack(CCA)security.The protocol is provably secure in the CK+ model which provides the strongest definition of security for authenticated key agreement protocol at present.The protocol can provide weak perfect forward secrecy and resist key compromise impersonation and leakage of ephemeral key attacks.Compared with the existing ABAKA protocols,our protocol is more efficient in communication cost and obtains stronger security.