A video decoding method, comprising: decoding information on a quantization matrix (S1410) (S 1420); reconstructing a quantization matrix based on the information on the quantization matrix (S1440); generating a residual block for a current block based on the reconstructed quantization matrix; generating a prediction block for the current block; and reconstructing the current block based on the residual block and the prediction block, wherein the residual block is generated by performing inverse-quantization on a quantized coefficient of the current block using the reconstructed quantization matrix, wherein the information on the quantization matrix includes information indicating a prediction method of the quantization matrix (S1430) and further includes, based on the information indicating a prediction method of the quantization matrix, information representing a difference value between quantization matrix coefficients, wherein the reconstructing of the quantization matrix is characterized by including deriving a quantization matrix coefficient by using the information representing a difference value between the quantization matrix coefficients; and arranging the quantization matrix coefficients in the quantization matrix by up-right diagonally scanning the quantization matrix coefficients, wherein the up-right diagonally scanning arranges the quantization matrix coefficients along every up-right diagonal lines in the quantization matrix one by one from top-left to bottom-right direction, and starting from a lower-left position to an upper-right position for each up-right diagonal line. decoding information on a quantization matrix (S1410) (S 1420); reconstructing a quantization matrix based on the information on the quantization matrix (S1440); generating a residual block for a current block based on the reconstructed quantization matrix; generating a prediction block for the current block; and reconstructing the current block based on the residual block and the prediction block, wherein the residual block is generated by performing inverse-quantization on a quantized coefficient of the current block using the reconstructed quantization matrix, wherein the information on the quantization matrix includes information indicating a prediction method of the quantization matrix (S1430) and further includes, based on the information indicating a prediction method of the quantization matrix, information representing a difference value between quantization matrix coefficients, wherein the reconstructing of the quantization matrix is characterized by including deriving a quantization matrix coefficient by using the information representing a difference value between the quantization matrix coefficients; and arranging the quantization matrix coefficients in the quantization matrix by up-right diagonally scanning the quantization matrix coefficients, wherein the up-right diagonally scanning arranges the quantization matrix coefficients along every up-right diagonal lines in the quantization matrix one by one from top-left to bottom-right direction, and starting from a lower-left position to an upper-right position for each up-right diagonal line. <EOS>