Abstract: To solve the problem of unstable link and low reliability in vehicle ad hoc network (VANET), we propose a relay forwarding scheme based on weighted clustering. In the scheme, we first present the weighted cluster algorithm to improve the stability of the communication link and introduce the relative vehicular confidence distance, relative achievable rate and connectivity as clustering properties and select the optimal cluster head as a relay in the ascending order of their property weight. And then, the bidirectional DF protocol is adopted to enhance the reliability of vehicle to vehicle communication under the NaKagami-m channel. Numerical results show that the stability of the proposed algorithm cloud improve 8 seconds compared with the lane based cluster algorithm. The outage probability of bidirectional DF protocol reduces 6% compared with AF protocol.