To obtain the moon elevation with high accuracy, it is necessary to accurately estimate the pointing error of laser. During the on-orbit operation of the lunar orbital laser altimeter (LOLA), the laser pointing at night deviates from that during the daytime due to the large temperature difference between day and night. This study first establishes a theoretical model of the detector’s received energy when the spot deviates from the center of the receiving field of view. Then, it analyzes the theoretical relation between the spot’s offset and relative received energy based on this model, and puts forward a laser pointing error estimation method based on spot energy. Subsequently, using the energy data generated when LOLA passed through the Aestuum region during the mapping orbit (12 months), this energy data is combined with the proposed estimation method, and laser pointing errors of LOLA at night in moon are estimated to be 140.62 μrad along the orbit direction and -413.17 μrad in the vertical orbit direction, which are consistent with the results derived from LOLA earth scanning experiment and orbital intersection altitude data.