Mesh networks are autonomous, where each node is not only a terminal but also a router. Due to this feature, mesh networks demand nodes to cooperate with each other to improve the availability and the performance, as well as to enforce the security. A cooperation enforcement mechanism based on a node trust model is addressed in this paper in order to evaluate the trustworthiness of neighboring nodes. Simulation results validate that the proposed mechanism can respond rapidly to the behaviors of other nodes, and significantly reduce packet loss rate when malicious or selfish nodes present.