An intraprediction/inter prediction method and apparatus is provided. In a method of intrapredicting an image processing unit of a current picture, the image processing unit including a plurality of sub blocks, a first prediction value of the image processing unit is generated by intrapredicting each of the sub blocks using pixels neighboring each of the sub blocks. A second prediction value of the image processing unit is generated by intrapredicting each of the sub blocks using pixels neighboring each of the sub blocks included in the first prediction value. Accordingly, an intrapredicted value or an intrapredicted motion vector can be more accurately obtained, so that the compression rate of image encoding is improved.