In the 3D game, there are many NPCs for various purposes, and the variety of motion of these NPCs increases the immersion feeling of the game. In this paper, we propose a noise - based motion editing technique that can add diversity and naturalness to the motion of NPCs. In the area of computer graphics, noise function has been used as a classical method of applying the naturalness of the animation. We extract these noise functions from existing motion signals and control them to make many similar motions naturally.