Abstract: Many simulation scenarios based on different numbers of source nodes（namely,the number of source-destination pairs） for Ad Hoc networks’ routing protocol AODV are designed. The number of source nodes is set as 10,20 and 30 separately,and the performance of the protocol under different scenario is compared and analyzed by simulation experiments. The results of simulation experiments show that the time-lag and routing load will increase along with the increasing of source nodes,while packet delivery fraction will decrease.