The dataset comprises multiple components aimed at evaluating and validating regional carbon and hydrological fluxes in the Yellow River Source Region (YRSR). Point‐scale carbon fluxes (NEE & GPP) Eddy‐covariance measurements at two flux towers in Maqu (Wei et al. 2021) and Zoige (Kang et al. 2014; Wang et al. 2016) provided daily‐resolution NEE and GPP data for 2008–2020. Long‐term spatial GPP dynamics (3 km resolution) Three remote‐sensing and model‐based GPP products were resampled to a common 3 km grid: MODIS MOD17A2H (8-day, global coverage) EC-LUE GPP (1 km, originally 1985–2015; Zheng et al. 2020), aggregated to 3 km Regionally calibrated CASA GPP (Chen et al. 2019), also reprojected to 3 km Developed GBEHM-Carbon GPP simulation Riverine carbon exports Dissolved inorganic carbon (DIC), dissolved organic carbon (DOC), particulate organic carbon (POC), and CO₂ fluxes from 254 daily sampling campaigns at 60 outlet locations across multiple river orders (Song et al. 2024; Zhang et al. 2020; Tian et al. 2019). Runoff and sediment simulations Modeled runoff and sediment‐yield outputs (daily or monthly) used for calibration/validation of hydrological and erosion models (see “Runoff_Sediment” folder). These files contain both simulated discharge and suspended sediment concentrations at key gauging stations within the YRSR basin. Together, these components enable comprehensive calibration and validation of water–carbon coupling models, supporting analyses of point‐scale flux variability, basin‐scale long‐term GPP trends, and coupled hydrology–sediment processes.