Abstract: Garment simulation can augment the fidelity of 3D human animation, but the collision detection and response it needs is too complex to be applied in a practical system. In this paper, a fast algorithm for collision detection and response between an active human body model and cloth is presented. The algorithm reduces the collision detection between human skin surface and cloth model to a simple distance measurement from particles on cloth model to human skeleton, via reconstructing 3D human body model. It significantly reduces the time complexity to O(n), where n denotes the amount of vertex on cloth. In order to ensure high accuracy of collision detection and high stability of the whole simulation system, cushion regions are established to forecast collision. Additionally, reasonable and efficient solutions for collision response are presented. Finally, a fast and stable 3D garment simulation system is realized and achieves realistic result.