The present invention discloses an image decoding method, the method including generating a candidate list including motion information derived from a spatial neighboring block and a temporal neighboring block adjacent to a current block; deriving motion information of the current block using the candidate list; generating a prediction block of the current block using the derived motion information; and updating the derived motion information in a motion information list, wherein the generating of the candidate list is performed in such a manner as to include at least one information of the motion information included in the updated motion information list in a block decoded before the current block.