Abstract: This paper proposed a new occlusion detection method for the true orthophoto generation that the primary problem is converted to computing the intersection points of the rays and horizontal planes by the rasterizing and iterating strategy.A moving horizontal plane is also applied to a completed detection,which includes examining the occlusions caused by the buildings' hiding each other.The experiments with the color aerial image data of the Kunming city shows that comparing with other two representative methods,this method can obtain more accurate results,and meanwhile the efficiency is satisfied.Additionally,the neighboring images are used for occlusion compensation,and finally the true orthophoto is generated.