Flood hazards are situations when land is submerged under the water and severely affect human livelihood such as life loss, property damages, etc. This study comprehends the flood assessment, identification, and estimation of areas prone to flooding. The pivotal aim of this study is to construct a flood susceptible zonation (FSZ) map of the Lakhimpur block of Assam that can be applied at the global, regional, and local levels to sustain human life and livelihood as well as to reduce and prevent damages caused by floods. GIS assimilated with MCDM and AHP model proved to be a handful of tools for identifying potential flood-affected zones in the study area. For this, eight parameters closely related to flood were collected from various online sources and subsequently generated FSZ applying GIS-MCDM and AHP technique using the software ArcGIS 10.8 and ERDAS IMAGINE 14. The constructed FSZ map classified into five classes, demonstrates that 78.85% of study areas are confined under high to very high susceptibility to flooding which is the central and western portion of the study areas and the rest are confined under moderate, low to very low susceptibility. The FSZ map was validated by performing the ROC-AUC curve and overall accuracy using historical ground truth data collected from Bhuvan NRSC. The resulting AUC value of 0.86 or 86% indicates a good accuracy of the FSZ map of the study area. The present research will serve as an adequate source of information for effective flood management, land use planning, etc. in various domains.