In this paper, the quality of 5 km and 10 km merged precipitation developed by China National Meteorological Information Centre is assessed based on the hydrological observed precipitation. Besides the U.S. National Oceanic and Atmospheric Administration (NOAA) climate prediction center satellite precipitation products (CMORPH) and the East Asian multisatellite integrated precipitation (EMSIP) developed by National Meteorological Information Centre are also assessed by comparing the two merged precipitation products. The data error of each precipitation product and its spatiotemporal variation characteristic are analyzed to verify the applicability of merged precipitation product in this selected region. The results show that the merged precipitation and satellite precipitation can well reflect the variation tendency of annual hourly precipitation. Four precipitation products all have a certain underestimate compared with the hydrological observed precipitation, and the underestimate of the satellite precipitation is larger. Merged precipitation has better quality, and the accuracy of the 5 km merged precipitation (R=0.81, RMSE=2.12 mm·h-1, RE=-5.4%) is better than the 10 km merged precipitation (R=0.78, RMSE=2.3 mm·h-1, RE=-5.1%). There is a great difference between the satellite precipitation and the hydrological observed precipitation. The correlation coefficient of CMORPH and EMSIP precipitation products is only 0.19 and 0.24, respectively. The error of each precipitation product has the same monthly variation tendency, and the error variation range of the merged precipitation product is obviously smaller than that of the satellite precipitation product. Besides, the quality variation of the four precipitation products in different rainfall level is also discussed, which shows that the correlation of the four precipitation products increases with the increase of precipitation. Merged precipitation products can accurately show the spatial structure and the central location of precipitation, 5 km merged precipitation takes great advantage in monitoring the severe precipitation events.