In the normal spectral radiance calibration of the internal illumination integrating sphere based on the spectral irradiance of the standard lamp, a deviation changing with wavelength exists in the ratio of instrument′s spectral radiance responsivities derived by two methods. The absolute radiance and irradiance radiometers based on the standard detectors are built up. By calibrating standard lamp of spectral irradiance and standard diffuser with these apparatuses at four wavelengths, it is found that the actual spectral irradiance of the standard lamp is greater while the actual bi-reflection distribution function (BRDF) of the diffuser is smaller than the self-calibrated value. After correcting the standard spectral irradiance and BRDF to the spectral radiance of the integrating sphere and the instrument′s spectral radiance responsivity, the ratio derives to constant 1. Analysis shows a combined standard uncertainty of 0.884%~1.217% for the spectral radiance and 0.768%~1.136% for the spectral irradiance measurement at the four wavelengths.