Development of sensing and composing methodology has been made for real-time simulation of natural human body motion and facial expression as one of the key technology for realizing a new human interface to communicate between human and agent in virtual reality space. In order to realize the simulation methods, we have thus far developed two systems separately; one is to simulate human body motion and the other is for facial expression. Both systems are based on actual measurement of human behavior. Details of the two systems are described with respect to measurement methods for human behavior and how to construct computer graphics in concern.