This paper examines the potential cost of offsetting increased flooding risk from climate change, based on simulations from a climate model of extreme floods out to 2050. The remainder of the paper is organized as follows: Section 2 describes the history of monsoon flood in Bangladesh. The future of monsoon flood in a changing climate is presented in Section 3. Section 4 summarizes the modeling and simulation to determine the impact of climate change on magnitude of floods and resulting vulnerable area and population. Section 5 describes the cost of climate proofing infrastructure in the flood plains, and Section 6 concludes the paper.