Abstract: Using the hourly precipitation observation data of automatic weather stations in Sichuan Province, the spatial and temporal distribution characteristics of 24-hour cumulative precipitation, frequency and intensity of short-term rainfall events during the main flood season （May -September) from 2010 to 2019 were analyzed. The frequency and extreme value distribution of short-term heavy rainfall events and their relationship with topography and altitude were discussed. The results show that the average 24-hour cumulative rainfall in Sichuan is basically more than 50mm, the northeast, southwest and south part of Sichuan Basin, and eastern Aba Prefecture exceed 100mm. The maximum is in Guang'an, reaching 175mm. The diurnal variation of the short-term heavy precipitation event in Sichuan area is manifested as a “V”-shaped structure of the peak phase at night. The event duration is mostly from evening to early morning, and the duration can be more than 10 hours, and last up to 22 hours. In the daily variation of extreme values of heavy precipitation events, the maximum frequency and precipitation showed a unimodal structure, and reached the maximum at 03: 00, and then gradually decreased to the valley at 15: 00, and then increased again. The precipitation intensity of the event showed an insignificant double-peak structure, reaching the valley values at 04: 00 and 16: 00, and reaching the peak values at 13: 00 and 18: 00. The diurnal changes showed a trend of first increasing and then decreasing, then increasing and then gradually decreasing. Short-term heavy precipitation events in Sichuan are closely related to the complex topography of the area. The active area of events are in the central Sichuan Basin from May to June, and in the Longmen Mountains in the western Sichuan Basin in July, near Ya'an and Leshan in August, and in the northern Sichuan Basin in September. The maximum hourly rainfall intensity of short-term heavy rainfall events can reach more than 80 mm, which occurs in the Longmen Mountains in the western basin and the southern region from July to August. With the increase of altitude, the frequency and days of short-term heavy rainfall events decreased gradually, and there was almost no heavy rainfall occurred in areas above 2000m ( except Emeishan weather station ).