With the continuous development of communication technology and with the wide application of portable equipment,wireless network,with low cost,convenience and easyuse,is attached importance.Based on this,Ad Hoc network is regarded as the optimal mobile network frame by its unique selforganization feature,however,congestion problem has been the factor for restricting the performance of Ad Hoc network property for a long time,Therefore,this paper firstly introduces Ad Hoc network,then analyzes the influence and cause for the congestion,studies Ad Hoc network congestion detection method,discusses its congestion control method and proposes the changing method from mobile Ad Hoc end to TCP congestion control improvement.