The Yangtze River Delta cities have high density of population and wealth，and climate change will add to great disaster risks.Vulnerability assessment is a tool for analyzing research of climate change policy，and will serve as an reference for adaptation management.Based on literature review and case study，this article constructs the assessment framework model of urban climate vulnerability from sensitivity and adaptation of cities in the Yangtze River Delta. Then，it assesses the urban climate vulnerability by using the Factor Analysis，and gets 5 main driving factors，it ranks the 16 cities and points out the climate vulnerability types of the 16 cities；It points out that the climate-proof adaptation and climate governance of the cities lag behind their social development，which can increase climate risks of the cities.It points out that in the future pressure of climate change，population growth，and urbanization，adaptation is a very urgent problem and gives some suggestions，such as considering climate proof in urban development planning，building up the mechanism of climate adaptation governance，etc.