Increasing urbanization and growth of population have increased the demand for various water resources especially the groundwater resources in Sagar Island, South 24 Parganas, West Bengal, India. Thus Groundwater resources should be managed properly with the application of various scientific propositions and modern techniques. In this research, identification of groundwater potential zonation (GWPZ) has been done using remote sensing–geographic information system (RS–GIS) technology and Fuzzy-AHP approach on a single platform. The main objective of the research is to use the Fuzzy-AHP approach to demarcate GWPZs utilizing 10 geo-environmental parameters. The study successfully identifies the GWPZs within the area of interest and categorizes GWPZs has been classified into five different classes following the groundwater availability that is very high potential 6.84%), high (36.23%), medium (27.68%), low (17.53%) and very low (11.72%). The originated GWPZ map has been verified using geophysical data collected from the field survey to test the model's performance. The validation results demonstrated that the applied technique yields considerably reliable findings that can aid in long-term planning and management for sustainable use of groundwater resources in different coastal tracts.