An video decoding apparatus including a parser which obtains bit strings corresponding to current transformation coefficient level information by arithmetic decoding a bitstream based on a context model; a parameter determiner which determines a current binarization parameter by updating or maintaining a previous binarization parameter based on a comparison of a threshold and a size of a previous transformation coefficient; a syntax element restorer which obtains the current transformation coefficient level information by performing de-binarization of the bit strings using the determined current binarization parameter and generates a size of a current transformation coefficient using the current transformation coefficient level information, wherein the current binarization parameter has a value equal to or smaller than a predetermined value.