This paper presents a method for texture mapping based on surafce split by octree. The method builds a poly-cube boundary box with all the leafnodes intersecting with surface model of the octree and then implements mapping a texture picture to the whole surface model via texture mapping in every unit cube. The traditonal two step texture mapping method casues great distortion when mapping textrue picture on some complex models because the shape of the boundary box is not similar with the model but the poly-cube boundary box can be quite similar with the model. The results show that the method is more efficient to some complex surface models than two step texture mapping method.