Aimed at the problems at present, the quasipassive exoskeletons mechanical structure is usually complex, and its control scheme is intricate. According to the data of human hip joints biomechanics, the relation trait between hip joints moment and hip joint's angle was found, and a new type of hip exoskeletons passive drive unit was designed based on this trait. The simulation experiment was implemented on the virtual prototype with ADAMS simulation platform, which verified the feasibility of the design scheme. Finally, the prototype was tested. The result shows that this walking assist exoskeleton can realize the actuation function in daily exercise.