The characteristics of Hopf oscillator are analyzed, and the feasibility of its application in gait generation of quadruped robot is discussed. Two kinds of CPG control networks are constructed by using Hopf oscillator and the structures of the two networks are analyzed and modeled. These two CPG can produce stable gait with strict phase relationship. The robot simulation software Webots and MATLAB are used for co-simulation. According to the output control signal of CPG network, each joint of quadruped robot is controlled and trot gait planning is realized. The simulation results show that the CPG network constructed by Hopf oscillator can achieve good gait planning for quadruped robot, which has the advantages of simple model and clear thinking. © 2020 Technical Committee on Control Theory, Chinese Association of Automation.