The Source Region of the Yellow River (SRYR) is the main runoff producing area and important water conservation area of the Yellow River Basin. It is of great scientific significance for understanding and exploring the land surface process and regional water cycle characteristics and revealing the impact of land-hydrological processes coupling over the SRYR. Based on the China Meteorological Forcing Dataset (CMFD), CPC Morphing Technique (CMORPH), Tropical Rainfall Measuring Mission (TRMM) and Global Land Data Assimilation System (GLDAS) precipitation from 2009 to 2018, the precipitation accuracy of four types of precipitation products is evaluated in this research. On this basis, the standalone Weather Research and Forecasting Model Hydrological modeling system (WRF-Hydro) model is chosen and driven by the optimal precipitation products to explore the applicability of this model in streamflow simulation over the SRYR. The results show that the four types of precipitation products have the ability to reflect the distribution characteristics of precipitation, while there are significant differences in quantity and detail. CMFD products perform better in capturing the evolution characteristics of the precipitation at different spatial and temporal scales. The correlation coefficient between CMFD products and gauge observation is 0.99, and the root mean square error is 0.25 mm. In terms of the ability to indicate precipitation, the overall performance of the four types of precipitation products presents that CMFD > CMORPH > TRMM > GLDAS and the average critical success index of CMFD is more than 0.93. The WRF-Hydro model calibrated by the sensitive parameters is with?good?performance in simulating monthly streamflow over the SRYR. The Nash efficiency coefficients (NSE) is above 0.92 during the calibration period, while the simulation results are significantly better in the high flow years than that in the low flow years with a NSE of 0.15 during the validation period, which is related to the non-linearity of precipitation and streamflow. This research scheme and results are potential to provide references for the large-scale watershed hydrological simulation and projection in the semi-arid region of the sub cold zone.