Abstract: To overcome the color distortion caused by wide color gamut in projection display system based on LED, a new color gamut calibration method is presented. In the time sequence display mode, in order to move the chromaticity coordinates of the trichromatic light to the proper position, other proportional trichromatic light is also introduced as an auxiliary light while a trichromatic light is adopted. A set of XYZ LED sensors is proposed to measure and feedback the chromaticity coordinates of trichromatic LED in real time so as to avoid the difference of LED consistency and the impact of environmental temperature fluctuation and the operation duration on the major wavelength and chromaticity coordinates of LED. The real-time color gamut correction was realized and the proper display color was achieved through the programming of the calibration algorithm.