Based on a detailed discussion about the conception of urban drinking water system adaptation,the paper established an adaptive capacity assessment index system and model of drinking water system in areas around Lake Taihu from the aspects of adaptation factors in water sources,water supply system,water user system,sewage treatment system and social system.According to the model and the sub-index and integrated-index,the drinking water system adaptive capacity,including spatial differentiation, types and influencing factors of cities around Lake Taihu area in Jiangsu Province,was evaluated.The results showed that: regions with strong adaptivity accounted for 29.1% with all five sub-systems high value;regions with middle adaptivity accounted for 41.2% with two types-relatively equal and uneven;regions with poor adaptivity accounted for 29.7%,mainly due to the technical sub-system is in low values and other sub-systems are not high.Therefore it is necessary to increase the differentiation enhancement of the adaptive capacity of each sub-system.