Two-Party authenticated key agreement protocols are constructed mainly based on the traditional public key cryptography and identity-based public key cryptography. The certificateless-based authenticated key agreement protocols have the advantages of avoiding the complexity of identity management in the traditional certificate-based schemes, as well as the key escrow issues inherited in the identity-based schemes. In 2007, Park et al. proposed a certificateless-based public key encryption scheme which is provably secure against chosen plaintext attacks in the selective-ID security model (IND-sID-CPA). Inspired on such a scheme, this paper presents a two-party certificateless-based authenticated key agreement scheme and gives the comparisons with other comparable schemes in security and efficiency. The new proposed scheme achieves almost all of the desired security attributes, especially the Perfect forward secrecy, PKG forward secrecy, Known session-specific temporary information secrecy and Key escrowless. Meanwhile it keeps the nice efficiency.