In order to explore the choice of white balance point in laser display, the influence of white balance point change on the color gamut in three primaries laser display was studied based on the color mixing theory and stereoscopic color gamut algorithm. Taking D65 color gamut as the standard, the appropriate white balance point selection range of laser display system was obtained by combining with color gamut coverage. The results show that when the white balance point is on the blackbody locus, the best choice of color temperature is around 6500K under different wavelength combinations. Further, considering the situation that the white point deviates from the blackbody locus, the appropriate selection range of white balance point of laser display system under different wavelength combinations can be obtained. These results can provide theoretical basis and reference for the selection of white balance point of display system.