Based on daily precipitation data from 126 national meteorological stations in Yunnan Province from June 2023 to June 2025, this study evaluated the applicability of Fengyun-4B (FY-4B) quantitative precipitation estimation (QPE) daily precipitation products over Yunnan Province using the correlation coefficient (CC), root mean square error (RMSE), relative bias (RB), probability of detection (POD), false alarm ratio (FAR), and critical success index (CSI), and compared FY-4B QPE with Global Precipitation Measurement Integrated Multi-Satellite Retrievals (GPM IMERG) and climate hazards group infrared precipitation with station data (CHIRPS) products. The results show that the precipitation detection capability of FY-4B QPE is superior to that of GPM IMERG and CHIRPS, with the highest CSI (0.44) and the lowest FAR (0.44). However, it exhibits a certain degree of precipitation underestimation (RB=?0.15). In comparison, GPM IMERG has the highest FAR (0.53), and CHIRPS shows a relatively low POD (0.41). FY-4B QPE exhibits a pattern of higher precipitation over the southwest and lower precipitation over the east of Yunnan Province. The precipitation detection capability in southwestern and southern Yunnan is superior to that in the central and eastern regions. The southwestern and southern areas, covering approximately 31% of the province, have an average CSI that is 0.14 higher than that of the central and eastern regions. The 500 to 1000 m elevation range is the optimal application area for FY-4B QPE. FY-4B QPE performs best under light rain, with pronounced underestimation under heavy precipitation. FY-4B QPE is sensitive to seasonal variations, with strong detection capability but a tendency toward underestimation in summer, while overall accuracy decreases somewhat in winter. The evaluation results can provide a scientific reference for the research and operational applications of FY-4B QPE for precipitation monitoring in complex terrain areas of Yunnan Province.