In this paper, we propose a novel scheme to improve the performance of wireless local area networks (WLANs) in error-prone environment. The key idea of the scheme is to partition a frame into several blocks, and then to retransmit only the blocks that encountered errors in the previous transmission. To evaluate the performance of the scheme, we also develop an analytical model to analyze the saturated throughput performance. Extensive simulation and analysis results show that, 1) the proposed scheme can significantly improve the throughput performance of WLANs in error-prone conditions; 2) an optimum block size can lead to the maximum saturated throughput; 3) with an appropriate block size, the throughput can increase with the increase of the size of a frame, even in error-prone environment; and 4) the analytical results are highly accurate.