To meet the requirement of high precision measurement (0.2×10-6) of refractive index homogeneity of optical glass, the uncertainty caused by temperature of measurement environment should be less than 0.05×10-6. Uncertainty analysis caused by temperature is taken for five error sources. The result shows that when the radial temperature difference of air, flats, oil, and component in the measurement cavity is ±0.01 ℃, the uncertainty caused by temperature is 0.031×10-6, which can satisfy the precision. Important data are offered for high precision measurement of refractive index homogeneity of optical glass, and useful advices are given for the improvement of laboratory enviroment.