Data-scarce often limits the potential of hydrological modeling around the world. In ungauged areas, ground-based observations (OBs) or reanalysis products could be used to replace missing data. Reanalysis datasets provide a reliable reanalysis of climate input data for hydrological modeling. However, the performance of different datasets needs to be thoroughly tested. This study evaluates the performance of China Meteorological Administration (CMA), Climatic Research Unit Global Climate Dataset (CRU), and NASA Prediction of Worldwide Energy Resources (NASA Power) reanalysis precipitation reanalysis products by using data from 3 meteorological station in headwater area of Yangtze River over the Qinghai – Tibetan Plateau and were used as input data for the SWAT model for runoff simulation and evaluation, respectively. This research can provide a reference for selecting meteorological data products and optimization methods for hydrological process simulation in areas with few meteorological stations.