In this paper, a framework of 3D Real-time Garment Simulation System for character animation is presented .For the problem of computational efficiency and stability for cloth physical modeling, we proposed a cloth mass-spring model based on constraint. Take geometry sphere and cylinder as example to explaining the whole strategy which used to dealing with cloth deformable bodies colliding with environment object. We described the procedure of physically based simulation, and illustrated the result and analysis of the experiment. By using the technique of parameterized human body modelling, virtual try-on was realized with the different shape of virtual character. Finally, integrating the techniques of character animation, physically based cloth simulation and non-precise deformable object collision handling, we create the real-time simulation animation of virtual character.