The chief objective of wireless sensor networks designing is to pr ol ong the lifetime of networks, and topology control is the basic support for the objective. Aiming at the defect is that high redundancy of connectivity or low r obu st of structure in traditional methods, the problem was transformed into a model of multi-criteria minimum spanning tree ultimately, and a genetic algorithm wa s designed to deal with the model. A topology control method based on genetic alg orithm was proposed in this paper. The result of simulations suggests a topology with low total power consumption, high robust structure and low contention amon g nodes can be obtained by this method, and the lifetime of networks can be prol onged on the topology.