A method is proposed to measure the spectral modulation transfer function (MTF) of color displays. The spectral MTF is defined as the absolute value of Fourier transform of the spectral line spread function (LSF) on displays. In order to obtain the spectral LSF, we measure the spectral radiance distribution of a displayed single line of various colors. The measurement system is constructed with a charge coupled device (CCD) and three band-pass filters. Three-bands CCD values can be transformed to 81-bands spectral radiance using the transformation matrix generated by multiple linear regression analysis. Using our proposed method, we measured the spectral MTFs of a color liquid crystal display (LCD). The MTF characteristics of the LCD were measured as device-independent value.