This paper builds a water supply reliability econometric model to analyze climate changes and adaptation impact factors on water supply reliability of irrigation wells by using 100 villages’ three-year(2010-2012) field survey data of five middle and eastern provinces of China.The results show that long-run climate change factors,adaptation measures,village-level organizations of irrigation management,as well as extreme climate factors affect the water supply reliability of irrigation wells significantly.Meanwhile,there are significant differences impacting different crops and provinces.This paper suggests that agriculture meteorological disaster monitoring and warning systems should be strengthened by increasing irrigation facilities construction and maintenance,promoting reform of agricultural irrigation water management system,and developing various forms of peasant cooperation organization in order to improve agricultural production capacity to adapt to climate change. This paper builds a water supply reliability econometric model to analyze climate changes and adaptation impact factors on water supply reliability of irrigation wells by using 100 villages’ three-year (2010-2012) field survey data of five middle and eastern provinces of China. results show that long-run climate change factors, adaptation measures, village-level organizations of irrigation management, as well as extreme climate factors affect the water supply reliability of irrigation wells significantly.Meanwhile, there are significant differences impacting crops and provincess.This paper suggests that agriculture meteorological disaster monitoring and warning systems should be strengthened by increasing irrigation facilities construction and maintenance, promoting reform of agricultural irrigation water management system, and developing various forms of peasant cooperation organization in order to improve agricultural production capacity to adapt to climate change .