Abstract: The impact of droughts on yields was analyzed by using the statistical regression model, based on yields data of wheat, maize and potato from 10 cities or leagues of Inner Mongolia, and temperature and precipitation data (1961-2008) from 58 meteorological stations. The results showed that the temperature increased during crop growth season in last 48 years. The average temperature of 10 cities during 2001-2008 increased 0.9℃ comparing to that during 1971-2000, the average precipitation reduced 489mm at the same time. The aridity index of wheat, maize and potato increased 1.29, 1.82 and 1.49, respectively.Additionally,it has been also revealed in the outcomes of pre-estimated yield that most of the regions would have a declining yield with increase intervals of the temperature at 0.2℃,0.5℃ and 1.0℃ .while the precipitation keeps at the climatological mean level.The more temperature rising,the more yield would decrease. Furthermore,the yield would increase with more rainfall while the temperature going up by 0.2℃ above the climatological mean temperature.Only with more than 20 percent increase amount of precipitation would the yield increase possibly when the rising temperature interval reaches to 0.5℃ With the temperature interval goes up to 1.0℃,most regions perform a decrease yield even with 30 percent increase of precipitation,just few of the regions show a little increase yield

Key words: font-family: "Times New Roman", mso-bidi-font-size: 12.0pt, mso-hansi-font-family: 宋体, mso-bidi-font-family: 宋体, mso-font-kerning: 1.0pt, mso-ansi-language: EN-US, mso-fareast-language: ZH-CN, mso-bidi-language: AR-SA, mso-fareast-font-family: 宋体">Temperature increasing, Drought, Aridity index, Precipitation, Yield