Based on the self-developed automated reflectance monitoring spectrometer (ARMS) and hyperspectral irradiance meter (HIM) in visible-shortwave infrared band, the automatic measurement of the reflectance of three gray-scale targets in Songshan Remote Sensing Calibration Field, China, was realized, and the data obtained by the self-developed instruments was compared with the data acquired manually by the ASD portable spectrometer. The comparison results of the two methods show that the relative deviation of the reflectance data is better than ±2% in the range of 400-1600 nm for non-atmospheric absorption band. Then the target reflectance data in the site acquired by the automated equipments from October 2019 to November 2020 was analyzed in details. The analysis results show that the target reflectance of Songshan field is changeable with the environment, and the change trend of reflectance is related to the wavelength range and the measurement area, while the standard deviation of reflectance is within ±2.5% in the whole band. The work provides a strong technical support for the automatic and high-frequency on-orbit radiation calibration based on the Songshan Remote Sensing Calibration Field.