Abstract: Data calibration algorithm for the enhancement of earth observe image was presented. A new BRDF model of earth objects was established for the calibration of earth observe image by the national metrology equipment. Through BRDF absolute calibration, the earth observe image can be appeared more true. This model colligated the BRDF of earth objects, solar radiance, the atmosphere status, the correct parameter of BRDF calibration and the space camera parameter. The output data of this model is the enter radiance data for the space camera. A kind of ground glass for architecture is measured and the correspond earth observe image is calibrated. After calibration, the chromatism of this image is improved by 3 and the luminance contrast of that is improved by 3.