The invention provides a processing method of monitored elevation data of an open mine pit slope based on a measurement robot. The method comprises the following steps: obtaining monitored basic data of the open mine pit slope, which is acquired by the measurement robot; establishing a model of a height difference between a distance measuring optical path curve of the measurement robot and the ground, and an atmosphere vertical refraction physical quantity gradient model on a distance measuring optical path; obtaining an instrument height and a beacon height of the measurement robot; calculating the height difference from a monitoring base point subjected to atmosphere refraction revising and a monitoring point according to an included angle, a slope distance and a horizontal distance from the monitoring base point to the monitoring point, an atmosphere refraction coefficient on the distance measuring optical path curve and the instrument height and the beacon height of the measurement robot; obtaining an elevation of the revised monitoring point according to the height of the monitoring base point, measured by the measurement robot, and the height difference between the monitoring base point subjected to atmosphere refraction revising and the monitoring point. The elevation data is processed by utilizing the method provided by the invention, the precision of the elevation data can be relatively greatly improved and the reliability of a monitoring result is improved, so that a foundation is laid for real-time early warning of landslip of the open mine pit slope.