This paper introduces the motion capture technology and its use in computer animation. Motion capture is a powerful aid in computer animation and a supplement to the traditional key-frame animation. We use professional cameras to record the body motion and facial expression of the actor and then manipulate the data in software to eliminate some occlusion and confusion errors. As to data that is still not satisfying, we use data filter to smooth the motion by cutting some awry frames. Then we import the captured data into Motionbuilder to adjust the motion and preview the real-time animation. At last in Maya we combine the motion data and character model, let the captured data drive the character and add the scene model and music to export the whole animation. In the course of computer animation, we use this method to design the animation of military boxing, basketball playing, folk dancing and facial expression.