This dataset includes the regionally-averaged monthly hydrological data in two karstic basins, southwest China which are processed or estimated for the manuscript entitled "A novel approach for assessing groundwater recharge by combining GRACE and baseflow with case studies in karst areas of southwest China" by Huang et al., 2022 (submitted to Water Resources Research, Major Revision). Basin description: The Wujiang River Basin (WRB, ~87,900 km2, ~70% karstification) and Xijiang River Basin (XRB, ~360,000 km2, ~44% karstification) are two typical karstic basins in southwest China. The Wujiang River is the largest tributary in the southern part of the upper Yangtze River. It is originated from the Wumeng Mountain in the Yunnan-Guizhou Plateau and flows from Guizhou to Chongqing. The Xijiang River is the largest tributary of the Pearl River (the largest river in southern China). It is originated from the mountains in eastern Yunnan and flows to Guangxi, Guangdong, and finally into the South China Sea. Data description: 1. TWSA (unit: mm in equivalent water thickness) is the average terrestrial water storage anomaly data obtained from three release 6 GRACE (Gravity Recovery and Climate Experiment) mascon solutions, i.e., the Center for Space Research (CSR) at the University of Texas (http://www2.csr.utexas.edu/grace/RL06_mascons.html), Jet Propulsion Laboratory (JPL, https://podaac.jpl.nasa.gov/dataset/TELLUS_GRAC-GRFO_MASCON_CRI_GRID_RL06_V2), and Goddard Space Flight Center (GSFC, https://earth.gsfc.nasa.gov/geo/data/grace-mascons). The anomalies were estimated by removing a mean background value during 2006-2012. 2. SMSA and SWSA (unit: mm in equivalent water thickness) are the soil moisture storage anomaly and surface water storage anomaly data based on the model simulations by WGHM (v2.2d) provided by Dr. Hannes Müller Schmied (email: hannes.mueller.schmied@em.uni-frankfurt.de) at Institute of Physical Geography, Goethe-University Frankfurt. The anomalies were estimated by removing a mean background value during 2006-2012. 3. Precipitation data (unit: mm/month) were based on the monthly gridded (0.5×0.5 degree) data product obtained from China Meteorological Administration (CMA, https://data.cma.cn/) which was interpolated from ground-based data measured by meteorological stations. 4. Groundwater recharge (unit: mm/month) was estimated based on the groundwater budget method, i.e., the summation of groundwater storage change (GWSC) and baseflow. GRACE-based recharge was estimated using the GWSC derived from GRACE TWSA, WGHM-simulated SMSA and SWSA and in situ-based reservoir storage data. Observation-based recharge was estimated using the GWSC based on in situ groundwater-level data and specific yield (or storage coefficient). Both GRACE- and observation-based recharge were estimated using the baseflow separated by a multiple linear regression using the in situ streamflow as predictand, and precipitation and water table depth data as predictors. Time span: 2003-2014. The time lable like "200301" means January, 2003. "200312" means December, 2003.