1. A moving picture coding device that codes a moving picture using a motion vector in units of blocks obtained by partitioning each picture, comprising: a motion vector predictor candidate constructing unit that derives first and second motion vector predictor candidates from the motion vector of one of the coded blocks neighboring the coding target block in the same picture as the coding target block, and derives a third motion vector predictor candidate from a motion vector of one of blocks of a coded picture different from the coding target block; a motion vector predictor candidate adding unit that adds the first to third motion vector predictor candidates satisfying a certain condition to a motion vector predictor candidate list; a redundant motion vector predictor candidate determining unit that deletes the second motion vector predictor candidate from the motion vector predictor candidate list when the first and second motion vector predictor candidates added to the motion vector predictor candidate list by the motion vector predictor candidate adding unit have the same values; a motion vector predictor candidate limiting unit that repeatedly adds a motion vector predictor candidate having a same value to the motion vector predictor candidate list until the number of motion vector predictor candidates reaches a certain number when the number of the motion vector predictor candidates added to the motion vector predictor candidate list is smaller than the certain number (a natural number larger than or equal to 2); a motion vector predictor selecting unit that decides a motion vector predictor of the coding target block based on the motion vector predictor candidate list; and a coding unit that codes information representing the decided motion vector predictor index in the motion vector predictor candidate list.