A method performed by a video encoding apparatus for encoding a current motion vector of a current block in a current picture, includes: encoding, into a bitstream, mode information for use in selecting a motion vector prediction mode among a plurality of motion vector prediction modes; and when the mode information indicating a first motion vector prediction mode among the plurality of motion vector prediction modes is encoded, deriving a set of candidate motion vectors from motion vectors of a plurality of neighboring blocks of the current block, and selecting a candidate motion vector from the set of the candidate motion vectors; setting the prediction motion vector of the current block into the selected candidate motion vector; and generating a differential motion vector of the current block by subtracting the prediction motion vector from the current motion vector, and encoding the differential motion vector into the bitstream.