Abstract: According to the application requirement of computer animation,this paper introduces a novel asynchronous gait model of anteroposterior sequence with the prior knowledge in the field of biology.And on this basis,this paper implemented a footprint constraints generation method.Firstly,the prior knowledge of the biology field was used to establish the asynchronous gait model of anteroposterior sequence,which was used to parameterized describe any gait pattern of quadruped.Secondly,the gait model can select the most suitable gait pattern with speed inputted,and deal with transition between different gaits.So the gait graph can be generated for the whole motion sequence.Finally,with the gait graph and speed inputted,we can generate the toe trajectories of quadruped for multi-constructions of environment,such as terrain,turning and so on.The experimental results show that with biological data,the input speed and environment constraints,the proposed method can quickly and efficiently obtain the toe trajectory of a quadruped.And the real constraints driven motion results can be calculated by locomotion method with our trajectories.