The target location accuracy is an important index to evaluate the performance of airborne electro-optical system. For the high-altitude airborne electro-optical system, the target location accuracy is not only affected by the comprehensive factors such as sensor, rangefinder, stabilization accuracy of load platform, stabilization accuracy and position accuracy of flight platform, but also affected by the atmospheric refraction. For the long-distance ground observation of high-altitude airborne electro-optical system, the impact of atmospheric refraction on target location is particularly serious. Starting from the influence mechanism of atmospheric refraction on target location, an atmospheric model was given to analyze the influence factors of atmospheric refraction. Based on the earth model between the sphere and the reference rotating ellipsoid, the atmospheric refraction error model was given. Finally, the influence of atmospheric refraction on target location was analyzed according to the proposed earth model of approximate reference rotating ellipsoid. The analysis results have important guiding significance for the atmospheric refraction correction of airborne electro-optical system for long-distance target location.