Abstract: At present, the results obtained by most methods for calculating lunar illumination conditions in the lunar polar exploration often have large errors, making them difficult to be applied in space mission planning and scientific research. Therefore, a real-time calculation method for illumination conditions in the lunar polar regions considering high-precision terrain was proposed in this paper. Based on the currently available highest resolution terrain data, the calculation results of illumination conditions at a specific location were achieved by searching the horizon and calculating the elevation angle with azimuth, and by combining the solar zenith angle and apparent solar disk diameter. This method provides accurate calculations of illumination conditions and allows for the customization of terrain search range and accuracy. Furthermore, it outputs illumination conditions for any desired time span. Based on the method, several locations in the lunar south pole were selected as candidate landing sites. The annual average illumination rate for each landing site at elevations of 2, 5, 8, 10, 15 m were calculated and the influence of elevations on the illumination condition were analyzed. The proposed study may provide a reference for the subsequent missions.