An image encoding/decoding method and apparatus are provided. An image decoding method according to the present disclosure comprises determining whether to apply intra prediction to a current chroma block based on information on prediction of the current chroma block, deriving an intra prediction mode of the current chroma block based on an intra prediction mode of a corresponding luma block corresponding to the current chroma block and intra chroma prediction mode information of the current chroma block, when intra prediction applies to the current chroma block, and generating a prediction block of the current chroma block, by performing intra prediction based on the intra prediction mode of the current chroma block. When the intra prediction mode of the corresponding luma block is not present, the intra prediction mode of the current chroma block is derived based on a default intra prediction mode.