To explore the security mechanism of the Internet of Things (IoT) perception environment, we perform a security research on the IoT on the basis of game algorithm. The dynamic game method of node cooperation is used in the experiments. Firstly, multiple report nodes are merged into a game party, and the dynamic game for two parties is established with the detection node. In the environment where the malicious nodes are dominant, the detection nodes collaborate, and the state of the unknown nodes is conjectured by the reputation value of the reporting nodes. The high trust reference report is used for the modification and reduction the weight of malicious nodes in the overall report, for node merging, and finally for bias equilibrium. The results show that cooperative game can significantly improve the success rate of incident monitoring and reduce the number of forged reports.