Abstract: The paper studies the case that the download time or download success rate gain brought by random network coding，compared to store-and-forward mechanism，on the file-sharing program and the impact of Bit Error Ratio（BER） on random network coding’s performance in a collision-based wireless Mesh network.The simulation results show that，in the Blind-Forward node collaborative manner，when the number of source node is 1 and source node is randomly placed，random network coding can make download time reduce 30% to 40%.Furthermore，when the number of source node increases to 2，and the source nodes is placed fixedly，in both Blind-Forward and Selective-Forward node collaborative manners，compared to store-and-forward mechanism，the random network coding is greater extent in reducing download time.