<p>This study adopts the Flood Vulnerability Index (FVI), using four multidimensional constructs of vulnerability, as a new comprehensive and spatially expressive approach to estimating flood vulnerability. This became imperative as previous studies with respect to flood vulnerability in Abeokuta, Ogun State, Nigeria have essentially focused on the physical risk factors of vulnerability. Other relevant environmental, social, and economic risk dimensions were not explored. They also did not analyse the risks using an index-based approach, which is a new method to flood vulnerability assessment. Relying on expert opinions, the study developed, screened and scoped the constructs, sub-constructs, and relevant indicators adopted during the field observation and survey. A sample of 380 households, premised on confidence level of 95%, in 20 selected communities, was adopted. After removing highly correlated variables, indicators were normalized using the Min-Max linear scaling, weighted, and vulnerability ultimately mapped. The total Flood Vulnerability Indices (FVI) estimated for the flood- prone communities reveal that 20% of the communities fall into the very high vulnerability category, 45% fall into the high vulnerability category, while the rest fall into moderate vulnerability category. The highlighted contributions of each vulnerability marker to the estimated FVIs and the complementary findings obtained through remote sensing help to further contextualise the priority vulnerability challenges that stymie sustainable development. The multi-dimensional approach to FVI adopted by the study lends itself as a guidance tool for future flood risk assessments and for monitoring dynamics along the four main variables adopted by the study over time in flood-prone communities.</p>