A method of performing color gamut conversion obtains an ICC profile from image data and extracts XYZ values of red, green, blue, cyan, magenta, yellow, and white of a target color gamut of an image and X′Y′Z′ values of red, green, blue, cyan, magenta, yellow, and white of a reference color gamut of a display device from the ICC profile. The method further calculates a reference color gamut applying matrix that converts the XYZ values to the X′Y′Z′ values, RGB values of red, green, blue, cyan, magenta, yellow, and white of the target color gamut, and R′G′B′ values of red, green, blue, cyan, magenta, yellow, and white of the reference color gamut using the reference color gamut applying matrix and a RGB-XYZ converting matrix. A look-up table including the RGB values and the R′G′B′ values is generated and the image data is compensated based on the look-up table.