The processing effect of excimer laser Direct Writing in the case of surface machining will show the phenomenon of uneven processing and inconsistent processing line width. etc. The main work of this study is to realize the monitoring and compensation of the machining position in the surface micromachining process of excimer laser. The reference distance is selected before the operation of the device, and the machining position of each moment is tracked during the operation of the device. When the machining point is located at the lower deviation point or upper deviation point of the surface bias, the electric pan is reverse compensated to pull the point back to the baseline. In this way, the equal processing distance of each moment is ensured, which means that the machining platform in real time with the same fluctuation changes on the surface of the workpiece, so that the size of the workpiece on the surface remains unchanged. In order to achieve this goal, the hardware scheme of compensation device is constructed, and the sensor parameter matching and follow-up tracking software are developed. A set of excimer laser surface micromachining compensation device which can be applied to the processing of metal and non-metallic materials is developed, of which the move speed is more than 100μm/s and the compensation error is less than 20μm. Furthermore, the compensation performance and compensation processing effect of the device are verified by experiments.The maximum deviation were greater than 20μm in 18 of 100 compensation performance tests, and 2 of those were over 30μm. The device is composed of six-axis electric translation table, motion control card, laser sensor head, Laser sensing controller and PC computer. Secondly, based on the MFC framework, the follow-up software of excimer laser surface machining is written by C + + language, and the control signal sent by the software can flexibly control the response of electric translation table.