Aiming at current situation of low efficiency and being affected seriously by the weather in photoelectric sunshine duration recorder calibration process, based on the technology of solar simulation, integrating sphere brightness smoothing, light absorption trap and multidimensional adjustment, a new indoor calibration method for photoelectric sunshine duration recorder is proposed and a photoelectric sunshine duration recorder calibration system is designed. Firstly, according to the composition and operating principle of photoelectric sunshine duration recorder, the overall design scheme of the photoelectric sunshine duration recorder calibration system is put forward. Secondly, the main technical specifications of direct radiation simulation system, scattered radiation simulation system and solarterrestrial relationship regulating system are studied and analyzed. Then, according to the correlation among the components of the calibration system, the calibration chain of the calibration system is established, and the calibration methods of the components of the calibration chain are studied, and the traceability of the calibration result is realized. Finally, the simulation error of the sunshine hours of the photoelectric sunshine duration recorder calibration system is verified with experiments. The experiment results show that the simulation error of the sunshine hours of the photoelectric sunshine duration recorder calibration system is 3.75% within 4 hours, which satisfies the calibration requirements of current photoelectric sunshine duration recorder.