Abstract: The sapping caused by prevailing wind erosion is one of the most important factors in the deterioration of earthen architecture ruins located in semi-humid areas in Qinghai Province. Based on the climatic data for many years in the area and sapping quantity of the ruins, in combination with the results of laboratory tests and simulation analyses using Fluent software in computational fluid dynamics, the influence factors for the formation and development of wind erosion diseases of the earthen architecture ruins are evaluated. Furthermore, the effect of wind velocity, duration and area of wind erosion on the sapping quantity of the ruins are assessed quantitatively according to the analysis principles of engineering geology and mechanics. This study may be helpful for prevention, monitoring and control of formation and development of sapping diseases, forecast of sapping quantity of specific wind erosion as well as its effect on the stability of the earthen ruins.