In the process of integrating sphere‘s luminous flux measurement, first need to check the integrity of the system,check the environment whether meets the requirements. Then close integrating sphere, make the system to zero, to eliminate the influence of dark current. And then measuring the absorption coefficient, use the reference standard lamp to system calibration, power supply provides a stable, suitable current/voltage, make the standard lamp to lighting normally under the stable measurement environment. The multiple reflections light in the integral sphere uniform distribution in integrating sphere , the reflectivity of the integrating sphere is higher，the energy loss in the process of reflection is also less, at the same time, the reflector for full wavelength has a better response. The spherical error integrating sphere should be controlled within a certain range. Spectrophotometer by using the principle of the photoelectric effect, voltage or current is proportional with the luminous flux, collect a unit area of optical signals in integrating sphere and converted into electric signal, through the signal processing system, calculate the corresponding numerical.