Near space communication network is an important part of the space information network in the future.There are a large number of bursty traffic in the near space and competitive multiple access protocol is the main measure to solve. In the simulation model, through the MATLAB simulation of the SoltALOHA (SALOHA) protocol and Non persistent CSMA (npCSMA) protocol, compare the properties with bursty traffic increases the change trend in the near space network. According to the simulation results, npCSMA protocol is more suitable for near space network than SALOHA protocol.