The compliant gait of quadruped bionic robot can effectively reduce the impact on ground,improve the coordination and attitude stability of robot motion.In order to realize the compliant control of quadruped bionic robot,two control strategies are adopted: 1)the virtual leg control to achieve the gait control; 2)The position control of leg joints to realize the foot force control.The first control strategy which adopt the ideal of virtual leg is decomposed into single leg support,forward velocity control and attitude control.The second control strategy which convert foot force control to foot velocity control,and then be realised by the position control of leg joints,realize the compliant gait mode of quadruped biological with the continuous foot position.The overall control performance is tested via simulation with matalb/simmechanics and trotting motion experiments conducted over rough terrain with a quadruped robot.Results turn out to be positive: the quadruped robot demonstrates successful trotting w ith 7 km/h speed in a repetitive,active-compiant and dynamically-balanced fashion.