An object of the present invention is to express a predicted picture signal with light overheads, and to provide motion compensation of different pixel accuracy. A moving picture encoding device 20 according to the present invention includes a motion vector detection means 32 for detecting a motion vector of a predetermined area to be encoded in a frame picture, a prediction means 33c for predicting the motion vector of the predetermined area to be encoded by using an encoded motion vector of a predetermined area in the frame picture, a determination means 33d for determining whether or not the motion vector detected by the motion vector detection means 32 is a predetermined motion vector set in accordance with the motion vector predicted by the prediction means 33c, and a switching means 33e for switching a method of calculating a motion compensation value of the predetermined area to be encoded depending on whether or not the motion vector detected by the motion vector detection means 32 is the predetermined motion vector.