We propose a secure deniable asymmetric one-round group key agreement protocol based on decisional Bilinear Diffie-Hellman Exponent (BDHE) assumption. This protocol enables a set of users to negotiate shared encryption and decryption keys, rather than establishing a common secret. Each participant can join a protocol session, authenticate messages for other group members, but receivers cannot prove to a third party that such group involvement occurred. For authentication, we employ a ring signature scheme and message authentication code.