A new bidirectional reflectance distribution function (BRDF) model of earth objects is established for the calibration of remote sensing image by the national metrology equipment. This model colligates the solar radiance, the atmosphere status, the object type, and the space camera parameter, etc. The output data of this model is the enter radiance data for the space camera. The remote sensing image can be appeared more “true” through this calibration. A kind of ground glass for architecture is measured and the correspond remote sensing image is simulated. After calibrated, the chromatism of this image is improved by 2 and the luminance contrast of that is improved by 3.