1. A motion vector detecting apparatus for calculating an absolute difference between each pixel value in a coding target block and each pixel value in a block as a candidate for a reference block in a motion vector search range, summing the calculated absolute difference of individual pixels for each of a plurality of subblocks obtained by dividing the coding target block, further summing the sum results, and obtaining a motion vector on the basis of one of the sum results in units of subblocks and the total sum result.