Abstract: Aiming at the spatial variability of soil moisture under the redistribution of rainfall by photovoltaic power stations in Inner Mongolia grassland and its impulse response characteristics to precipitation events,continuously observe the temporal and spatial characteristics of soil moisture under photovoltaic panels in grassland areas were continously observed,and analyze the relationship between meteorological factors and soil moisture under photovoltaic panel interference was determinded. Finally clarify the influence mechanism of photovoltaic panels on soil moisture impulse response was clarified through parameter estimation. The results show that the total water storage capacity of the soil under the front eaves of the photovoltaic panels is higher than the soil water storage capacity under the photovoltaic panels and the areas where photovoltaic panels are not installed. The soil water storage of each layer of the front eaves of the photovoltaic panel has a strong response to precipitation. The soil water storage in each layer under the photovoltaic panel has no obvious response process to precipitation;The correlation coefficients between atmospheric humidity and 0-10 cm,10-20 cm and20-30 cm soil water storage are 0.889,0.579 and 0.414;The pulse equation R~2 of the moisture content of the 10 cm,20 cm and 30 cm soil layer of the photovoltaic panel front eaves and the natural precipitation is 0.875,0.938,0.957,the replenishment of precipitation promotes the pulse responses of the 0-30 cm soil layer moisture. The water content of the 0-20 cm soil layer in the area where photovoltaic panels are not installed has a good response process to natural precipitation.