Abstract: In the report, a group was used as researching object, a continuous three-dimensional space model was constructed. In space, according to three flocking rules, the perception field of each individual was divided into repulsion zone, orientation zone and attraction zone, the formula of the effects of behavior zones on individual speed direction was established. The effects of three behavior zones on individual were abstracted as three forces, the individual’s total speed direction was determined by that of three forces, the weight factor of each force was proposed, and when it was iterated to step t, the total speed direction was calculated, and when it was iterated to step t+1, the position vector and speed vector of individual were calculated. Matlab was used to simulate the motion situation of flock motion behavior in three-dimensional space, and the results indicated the model constructed could effectively simulate the flock motion behavior of animal.