In this paper, we investigate an energy efficient transmission scheme for video streaming in buffer-aided relay networks. In order to minimize the average energy consumption, we propose an energy-efficient transmission algorithm (EETA), which selects either the source relay (S - R) or the relay user (R - U) link for transmission depending on the instantaneous channel state information as well as the queue state information, and which further determines the optimal transmission data rate for the selected transmission link. Moreover, the proposed EETA converges, and the average transmission data rates of the S - R link and the R - U link converge to the playback rate of the video stream, respectively. Simulation results demonstrate the advantages of the proposed algorithm.