An efficient method for rain simulation in 3D environment is proposed in this paper. By taking advantage of the parallelism and programmability of GPUs (Graphic Processing Units), real-time interaction can be achieved. Splashing of raindrop is simulated using collision detection, series of stylized textures and rotations of point sprites. To simulate wind-driven raining effect, the motion of particles can be freely controlled based on Newtonian dynamics. We can also control the size of raindrops dynamically by using different textures or changing the size of point sprites. To achieve living rendering of raining scenes, the effects have been applied such as lighting, DOF (depth of field). Many experiments have been done in 3D scenes with different geometries complexity and particle system complexity. The test results show that our method is efficient and is feasible to solve the problem of real-time rain simulation for 3D scenes with complex geometries.