The GaoFen-7 satellite (GF-7) is equipped with China’s first spaceborne laser altimeter, which is officially used for earth observation, then its measurement accuracy of surface elevation has attracted much attention at home and abroad. Three calibration methods for spaceborne laser altimeter: the terrain matching calibration method, the single laser footprint image calibration method, and the ground detector array calibration method were introduced systematically. The above calibration methods of spaceborne laser altimeter were also used to carry out calibration test for GF-7 spaceborne laser altimeter with the same set of data. After laser calibration, the elevation measurement accuracy of GF-7 spaceborne laser altimeter was evaluated and analyzed under the results of three calibration methods. The airborne LiDAR point cloud data was employed for accuracy verification. The results show that the spaceborne laser altimeter calibration method based on ground detector array has the highest accuracy, which spaceborne laser elevation measurement accuracy of GF-7 laser beam 1 is 0.177 m, and the laser beam 2 is 0.157 m. Limited by the elevation accuracy of the reference topography data for spaceborne laser altimeter calibration, the elevation measurement accuracy of the other two spaceborne laser calibration methods is relatively low, which can just achieve 0.8 m.