In the field of rehabilitation, there is a great demand for an automatic and quantitative evaluation system. The balance ability is an essential factor for motor function evaluation related to posture control. Although balance ability is assessed using various indices in current clinical situations, most of previous studies developing an automatic evaluation system have used only a single particular index for balance evaluation. In this study, we developed a system that evaluates whole-body motor function using multiple indices based on the trajectory of the center of mass (CoM) and the motion smoothness. The system is inexpensive and little physical burden because the evaluation indices are calculated from the skeleton tracked by Kinect in a game environment. We attempt to capture the differences in individual motor functions which are difficult to be detected by qualitative visual observation.