Based on the daily surface precipitation data of 103 meteorological observation stations in Inner Mongolia from 1981 to 2018, the linear trend analysis method was used to analyze spatial and temporal climate characteristics of precipitation, precipitation days and precipitation intensities in Inner Mongolia. Results show that:the precipitation and number of precipitation days of all grades show weak decreasing trends, and the interannual variations of precipitation intensity of each grade was not significant. However, the interannual fluctuations of precipitation of each grade in the humid region is obvious, and the interannual fluctuations of moderate-rain intensity in arid region are significantly greater than that in other climatic areas. The average contribution of each grade of precipitation was light rain > moderate rain > heavy rain, but the regional distribution is uneven. The contribution of light rain days in each climatic area is about 80%-90%, and the proportion of light rain is gradually increased from the humid area in Northeast Inner Mongolia to the arid area in Northwest Inner Mongolia. The spatial distributions of all precipitation grades show a spatial distribution characteristic of decreasing from east to west in Inner Mongolia. The high-value areas of precipitation and precipitation days are mainly distributed in the northeast region, and the high-value areasof precipitation intensity are mainly distributed in the southeast region.Since 2010, the light rain amount and number of light rain days in the northeastern and central west of Inner Mongolia have decreased, while the light rain intensity showed an opposite pattern.In the northwest of Inner Mongolia, the precipitation and intensity of all grades have increased, and the increaseing in precipitation, precipitation days and precipitation intensity of heavy rain were particularly significant.