In depth image acquisition process due to the impact of the device itself and acquisition environment, the image obtained has a large number of empty,it is difficult to extract accurate depth information to solve the problem,a new method is proposed to solve the void in the depth image,which is simple and easy to be analyzed.First, expansion,corrosion,opening and closing operations and other basic algorithm are used to fill the empty part,and then through the bilateral filtering to make the image smooth.Experimental results show that the proposed method can effectively fill the holes in the depth image,and it is more clear and easy to extract reliable information than the original image.