Provided are methods and apparatuses for encoding and decoding a motion vector including a method of decoding that includes obtaining a current coding unit hierarchically split from a maximum coding unit according to a current depth, obtaining a prediction mode information of a current prediction unit in the current coding unit from bitstream, when a prediction mode of the current prediction unit is inter-prediction mode, determining motion vector predictor candidates from among motion vectors of neighboring prediction units adjacent to the current prediction unit, and determining a motion vector predictor of the current prediction unit from among the motion vector predictor candidates, wherein the neighboring prediction unit comprises a first block directly to the left side of a leftmost block among blocks located directly to a bottom side of the current prediction unit and a second block located directly to a upper side of the first block.