Abstract: The simulation of the wet road will greatly enhance the reality of a raining scene.By analyzing the physical mechanism of wet effect,we propose a double-reflection model of the wet road.Based on the subsurface scattering theory and the Torrance-Sparrow lighting model,the realistic reflections of the surrounding scene on the wet road are simulated.The reflection and refraction rays are traced with a novel path tracing algorithm.By incorporating the GPU technique,various conditions of wet road can be rendered in real time,and the results are quite realistic.