Disclosed herein is an image encoding/decoding method and apparatus. The image decoding method includes obtaining subblock based transform (SBT) use information, obtaining at least one of SBT division information, SBT division direction information or SBT position information, when the SBT use information indicates use of an SBT, and performing the SBT with respect to a current block based on at least one of the SBT division information, the SBT division direction information or the SBT position information. The SBT use information may be obtained when a width of the current block and a height of the current block are less than a maximum transform size.