Abstract: An integrating sphere photometer spectral response measurement method and system. The system comprises an integrating sphere photometer and three or more reference light sources having different peak wavelengths. The integrating sphere photometer consists of an integrating sphere (1) and a broadband photodetector (2), and the broadband photodetector (2) is mounted on the sphere wall of the integrating sphere (1). Emergent light of the reference light sources is incident to the integrating sphere (1); the total spectral radiation flux Pi(?) (i=1, 2, . . . n) received by an integrating sphere photometer system is acquired; the response Mi (i=1, 2, . . . n) of a photometer of mixed light in the integrating sphere (1) is read by means of the broadband photodetector (2); an equation set is established; and the spectral responsivity Srel(?) of the integrating sphere photometer is obtained by means of numerical solution.