Abstract: In the context of climate change, droughts index was calculated by using precipitation and temperature data in Fangxian county in 50 years（1961-2010）. The droughts were discussed and the effects on agricultural yields were analyzed through utilizing the index in Fangxian county. The results showed that droughts index change has an increasing trend in crop growth season and growing seasons before winter. The main reason lies in that temperature change showed increasing trend and precipitation showed decreasing trend. The droughts index change showed a reducing trend in summer, and the main reason is that temperature change showed a decreasing trend while precipitation showed an increasing trend. The droughts index change will affect food crop output, wheat yield and rice yield in Fangxian county. The research can be used as a scientific basis for the adverse effects study of climate change to agriculture. 

Key words: Climate change, Droughts index, Variation tendency