The utility model discloses an earth's surface height measurement auxiliary device and earth's surface height measurement device, the earth's surface height measurement auxiliary device include: frame and installing at the planar a plurality of support columns of the side of frame and vertical frame frame place, wherein at least one support column be with side sliding connection's slip support column, be equipped with in the frame and be used for the holding to survey the gliding bilateral slide rail of measuring with radar antenna device, the bilateral length of measuring the slide rail is greater than the length of surveying with radar antenna device, both sides measurement slide rail closely spaced in the width of detection with radar antenna device. The utility model provides an earth's surface height measurement auxiliary device through the slip support column, can adjust the height with the earth's surface to make detection for the radar antenna device of holding in the slide rail is measured to the frame both sides slide with horizontal plane keeping parallelism ground, thereby reduce the error that leads to because of the external force factor in the at utmost in the detection process, with the accuracy of guaranteeing experiment in the at utmost.