Abstract: In cooperative networks with automatic repeat request (ARQ), the multiple-rounds retransmission is used to improve the reliability at the cost of additional delay. In this paper, a cross-layer cooperative strategy is investigated in ARQ cooperative networks for the case that relay nodes do not have ability of signal combining reception. A selection cooperation scheme is proposed, in which both the decoding set and the selection of best relay are changed dynamically during each round of retransmission. In Rayleigh fading channels, the proposed scheme can achieve optimal diversity-multiplexing-delay (D-M-D) tradeoff without increasing the receiver complexity of relay nodes. Simulation results show that the outage probability performance of the proposed scheme is close to that of the scheme using combining reception at relay nodes. It achieves better tradeoff between the receiver complexity and the system performance.