The invention discloses a balanced-load wireless multi-heterogeneous-network access selection method. The balanced-load wireless multi-heterogeneous-network access selection method solves the problem that due to the fact that in the existing heterogeneous network access selection technology, different QoS demands of different services are not considered, resource waste is caused, system benefit is low, and network load difference is large. The balanced-load wireless heterogeneous multi-network access selection method comprises the steps that firstly, a judgment factor in network parameters is selected, and a network selection utility function is constructed; secondly, different judgment factor weight values are distributed to different services according to the different QoS demands of the different services; thirdly, when a service reaches, alternative networks which cannot meet the QoS demand of the service are removed, and the evaluation function value of each judgment factor in other alternative networks are worked out; fourthly, the evaluation function value of each judgment factor and the weighted value of each judgment factor are introduced, and the utility of each alternative network is worked out; finally, the network with the highest utility is selected for access. According to the balanced-load wireless multi-heterogeneous-network access selection method, under the condition of multi-heterogeneous-network coverage, the performance advantages of the different networks are utilized, the optimal network is selected for a user, the load of the network is balanced at the same time, and resources are brought into full play.