Collision Detection is one of the key issues on large-scale scenes roaming and it plays important part in the computer application and virtual reality. For the OBB bounding box algorithm in collision detection, this paper introduces a method based on the virtual occluders, which constructs the simple virtual occluders for OBB bounding box and realizes collision detection through intersection test between the virtual occluders and the OBB bounding box. This method rules out the objects without collision possibility and reduces the calculational works of the intersection test, thus it reduces the calculation of collision detection, and supply important experiment to research later. Tests show that the method can improve the speed of collision detection.