Since the coverage of wireless sensor network nodes is limited,the transmission of multi hop routing is adopted.The multi hop routing of wireless ad hoc networks is realized by common nodes cooperation and selecting different forwarding nodes will have a different effect upon the information transmission.By analyzing the network adaptive congestion control with different routing algorithms such as the flooding routing and the shortest path algorithm,the performances of network and congestion control with different kinds of routing algorithms were studied.According to the relationship between hop count and cache occupied,a kind of improved shortest path algorithm based on the performance function of node hop count and cache occupied was proposed,where the node with minimum value of function was selected as the forwarding node.Experiment examples were used to compare the network performances of the shortest path algorithm and the modified routing algorithm.It is shown that the modified one has better network performance and service quality than the shortest path algorithm.