Recent research on flood risk modeling has greatly advanced our understanding of the physical characteristics of flooding, it potential damages and adaptation measures. However, there are still a number challenges remaining, especially in urban developing areas, where the potential damages of devastating flooding events are proportionately higher than that of the rural areas. The uncertain nature of climate change and variability (e.g. sea level rise, precipitation and storm surge), coupled with the anthropogenic influences (e.g. land use change and land subsidence) in urban areas, may significantly exacerbate future flood risks, especially in developing nations. This talk will draw upon the presenter’s research experience and look at the key challenges in the study of urban flood risks in an uncertain climatic future. Key topics to cover will include: (i) high resolution modeling of flood inundation; (ii) interaction between land surface modification and fluvial flood risk; (iii) modeling surface water/pluvial flooding. Applications to various environments will be presented, including the UK, China, Thailand and Yemen, highlighting the development and opportunities existing in developed countries, complexity due to human influences in developing countries, and the challenges for flood modeling in data spare regions.