Color gamut represents the capability of the display system to display colors. It is an important indicator of the display system. Color gamut is not only affected by each primary color but also related to the white point coordinates of the display system. Different standards have different reference white points, so it is necessary to study the influence of different white point coordinates on the color gamut of the display system under various conditions. By using the total differential formula, the factors affecting the stereo color gamut of the display system are divided into two parts: the direct part caused by the light source parameters and the indirect part caused by the white point color coordinate. Considering the addition of the two effects, a more accurate stereo color gamut can be obtained. For a light source that meets the Rec.2020 standard, the central wavelengths of the three primary colors are 630, 532, 467 nm, and the spectral width is 1 nm, every 0.01x color coordinate increases the stereo color gamut by 0.80%, and every 0.01y color coordinate reduces the stereo color gamut by -2.15%. When the assumption that the color coordinates of the white point remain unchanged is selected, the green spectral width has the greatest impact on the stereo color gamut, and a narrow spectral width of green light should be maintained to ensure a high color gamut. When the assumption of constant intensity is selected, the three primary colors have similar effects on the stereo color gamut. Considering that the red light has the least influence on the color coordinates of the white point, the spectral width of the red light can be appropriately sacrificed to balance the stereo color gamut and the spectral width.