Abstract: Upper Ganga basin (UGB) is highly stressed in terms of water resources due to uncontrolled population growth, urbanization and intense agricultural activities in the past four decades. Thus, understanding spatio-temporal variability in the water yield and water quality of this region is of paramount importance for sustainable development and management of its water resources. In the present study, distributed Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model is applied to compute water yield variability across the Upper Ganga basin at pixel scale. However, spatiotemporal variations in the important water quality parameters such as turbidity, fluoride (F), total coliform bacteria, pH, hardness (CaCO3), biological oxygen demand (BOD), and dissolved oxygen (DO%) are studied using an overall index of pollution (OIP) developed specifically for this basin. From the results, it is evident that the mean water yield has increased from 1239.92 mm in 1980 to 1754.59 mm in 2015. Similarly, water quality of the upper reaches of the basin has remained in the excellent to acceptable (OIP: 1.38–1.81) class from 2001 to 2012, whereas it has changed from the acceptable to slightly polluted class (OIP: 1.87–2.79) in the lower reaches. Varanasi is identified as the most polluted station in terms of water quality. Both water yield and water quality are highly variable in time and space in this region.