In order to solve the problems of low node coverage, wide transmission blind area and limited cluster head nodes in the deployment process of the Internet of things, a node coverage algorithm based on axis symmetry mechanism is proposed. First of all, an area coverage method based on axis symmetry mechanism is designed by using the scheme of equidistant segmentation. The primary segmentation of network area is realized by symmetrical distribution of cluster head nodes, which improves the efficiency of network initialization coverage. Then, in view of the disadvantages of the primary and standby mechanism, a cluster head polling method based on the hot standby mechanism is constructed by deploying multiple mirror nodes in the preheating mode, so as to reduce the transmission blocking due to the cluster head node restriction. At last, we use the quantization method to optimize the initial segmentation area, and propose a transmission optimization method based on the quantization deployment mechanism to further improve the network transmission capacity and improve the transmission efficiency of cluster head nodes. Simulation results show that, compared with the existing coverage optimization algorithm of improved ant lion algorithm and the coverage algorithm of wireless sensor network based on improved particle swarm optimization algorithm, the algorithm in this paper has the advantages of strong congestion control ability, high node coverage efficiency, low cluster head limited probability, and has strong practical deployment value.