High-precision self-calibration radiation reference source based on spontaneous parametric down-conversion is the research hotspot of satellite remote sensing calibration. The principle of two-channel self-calibration radiometer was introduced, and a set of experimental device was established. The experimental verification was carried out by comparing with traditional radiometric standard detector. Monochromatic uniform radiance light source with 736.9 nm laser was used by integrating sphere, then the radiance at the outlet of integrating sphere was detected by two-channel self-calibration radiometer and radiance standard detector respectively. The measured absolute radiances results were 4.69×10－9 W/(sr·mm2) and 5.19×10－9 W/(sr·mm2), and the relative deviation was 9.63%. The feasibility of the principle of two-channel self-calibration radiometer was verified.