In this paper, we present a new ID-based two-party authenticated key exchange (AKE) protocol, which makes use of a new technique called twin Diffie-Hellman problem proposed by Cash, Kiltz and Shoup. We show that our scheme is secure under bilinear Diffie-Hellman (BDH) assumption in the enhanced Canetti-Krawczyk (eCK) model, which better supports the adversary's queries than previous AKE models. To the best of our knowledge, our scheme is the first ID-based AKE protocol provably secure in eCK model. Categories and Subject Descriptors C.2.0 [Computer-Communication Networks]: General-Security and protection General Terms Security Keywords ID-based, Authenticated key exchange, BDH problem, Twin Diffie-Hellman