Abstract: The Sundarban Biosphere Reserve (SBR) region has long been subject to cyclonic storms and severe flooding, resulting in heavy rainfall, flooding, and banks collapsing. Different Cyclonic storms and river bank collapsing, the acute drinking water problem can turn into a chronic issue in events like Aila,Foni, Cider, Reshmi, Yash, Amphan, etc. Even after the flood water recedes, the tube well water remains undrinkable. The main focus of my research article is on the drinking water crisis and vulnerability in the western part of the Sundarban, consisting of four blocks: Sagar Island, Namkhana, Patharpratima, and Kakdwip. The Sagarcoloni and Ghoramara of Sagar Island, Pailaghery and Amaravati of Namkhana, Gobardhanpur and Dakshin Sibganj of Patharpratima, Chandipur and Akshanagar of Kakdwip have been selected for intensive household surveying. After house-hold surveying of 446 households in the sample villages, the sea-facing or creek-facing villages have caused a crisis of pure drinking water due to not only physical but also social as well as economic vulnerabilities, i.e., literacy, awareness, occupation, female literacy, poor communication due to creek-netting location, etc. Thus, socio-economic vulnerability assessment has an important role to play in determining the drinking water vulnerability in this part of West Bengal's Sundarban.