In view of the phenomenon of simultaneous rain and heat and frequent flood and drought disasters in Jialing River Basin, in order to quickly and accurately grasp the precipitation and drought situation in the basin, the multi temporal and spatial scale inversion of Jialing River Basin is carried out by using the gridded IMERG satellite precipitation data with wide coverage and high resolution, and the standardized precipitation index (SPI) is used to monitor the drought in the basin based on the satellite precipitation data. The results show that: 1) according to the calculation results of classification indicators and statistical indicators, IMERG-F in the three satellite precipitation data can more accurately reflect the daily precipitation in the basin, and the cc with ground precipitation data is 0.737, which overestimates the ground precipitation by 2.6% as a whole, and has the application potential in drought monitoring. 2) The SPI indexes driven by three kinds of satellite precipitation data have some differences in drought monitoring. The SPI index driven by IMERG-F maintains high consistency with the SPI index driven by ground precipitation data (CC > 0.9). Compared with the near real-time product IMERG-F, it can more accurately show the dry and wet characteristics of the watershed. 3) The ability of satellite to identify precipitation and drought monitoring is affected by topography. IMERG satellite precipitation data has good applicability in plain and hilly areas.