Climate change is an inevitable trend,which challenges security of water resources in China,especially in cities.Assessing vulnerability of water resource to climate change in cities has important role for policy makers. The paper constructs a vulnerability function,including exposure,sensitivity and adaptive capacity,according to the vulnerability concept proposed by IPCC,establishes an assessment indicators system of water resources to climate change in cities,and analyzes vulnerability features of Chinese cites based on 655 cities’data in 2006.The vulnerability assessment results show that there are distinctive differences among all the cities,between east,central and west cities,between ordinary,big and mega cities,while there is no statistical significant difference between north and south cities.Based on the research,the paper suggests that strategic emphasis should focus on the central cities and ordinary cities Climate change is an inevitable trend, which challenges security of water resources in China, especially in cities. Assessing vulnerability of water resource to climate change in cities has important role for policy makers. The paper constructs a vulnerability function, including exposure, sensitivity and adaptive capacity, according to the vulnerability concept proposed by IPCC, establish an assessment indicators system of water resources to climate change in cities, and vulnerability study of features of Chinese cites based on 655 cities’data in 2006. vulnerability assessment results show there there are distinctive differences among all the cities, between east, central and west cities, between ordinary, big and mega cities, while there is no statistical significant difference between north and south cities.Based on the research, the paper suggests that strategic emphasis should focus on the central cities and ordinary cities