Small-size embodied interaction robots are required for use in home. These robots are expected to shake hands with human to promote embodied interaction. Therefore, in this paper, we develop a small-size handshake robot system for a generation of a handshake approaching motion. The handshake approaching motion has two motions. The first motion is a handshake request motion that the robot stretches its hand to a human as requesting a handshake. The other motion is a handshake response motion in which the robot responds a handshake when the human requests a handshake to the robot. In this robot system, a human hand position is estimated by using an image processing which is combined with a 3D arm model, and handshake approaching motions are generated using the estimated hand position. The effectiveness of the small-size handshake robot system is demonstrated by sensory evaluation of these handshake approaching motions.