The present disclosure discloses a colorimetry calculation method for a display. The display includes a quantum dot backlight module and a first polarizer, wherein the quantum dot backlight module includes a light guide plate, a quantum dot thin film layer, and a backlight. The method obtains the correction spectrum of the quantum dot backlight module, and obtains the true spectrum of the quantum dot backlight module when the first polarizer is arranged on the light exit side of the quantum dot backlight module based on the correction spectrum and the measurement spectrum, that is, the modified spectrum, so as to accurately simulate the chromatic offset phenomenon due to the secondary excitation of the first polarizer, and provide the basis for the quantitative design of the display including the quantum dot backlight module. The present disclosure also discloses a chromaticity calculation method of a display.