Under the background of global climate change and accelerating urbanization, urban flood disasters occur frequently, causing serious economic losses and casualties. This paper systematically introduces the flood disasters in China"s typical cities in recent years, and shows that the flood disasters bring huge casualties and economic losses. As a non-engineering flood control measure, risk assessment is the primary work of urban flood risk management. Accurately and efficiently grasping the characteristics of flood process can provide scientific basis for disaster prevention and mitigation. The concept and content of urban flood risk assessment and zoning are systematically sorted out. The commonly used risk assessment methods include mathematical statistics, uncertainty analysis, remote sensing image assessment, index system assessment and scenario simulation assessment. The common methods of risk partition include threshold method, empirical formula method and physical mechanism method. The application range, advantages and disadvantages of the common methods of urban flood risk assessment and zoning are discussed.