The present disclosure provides a video encoding/decoding method including: selectively frequency transforming a first residual block generated by subtracting a predicted block from a current block, generating a first quantized block for the first residual block or the frequency transformed first residual block, generating a second quantized block, if the first quantized block is a quantized first residual block from quantizing the first residual block, through selectively performing a secondary prediction on the quantized first residual block by using a secondary predicted motion vector set, encoding information on whether the frequency transforming is performed and selectively encoding information on the secondary prediction, encoding the first quantized block or the second quantized block into a bitstream, and decoding the same.