There is provided an image encoding/decoding method and apparatus. An image decoding method according to the present invention may comprise reconstructing a most frequent mode (MFM) indicator indicating whether or not an intra prediction mode of a current block is a predetermined intra prediction mode, deriving, on the basis of the MFM indicator, the intra prediction mode of the current block, and generating a prediction block of the current block by performing intra prediction on the current block on the basis of the intra prediction mode.