Abstract: The evolutionary regularity of moisture and temperature during crop growing season and the response of regional crop yield to climate change were analyzed by using the data of meteorological observation and the statistics of bean and the main crop yield of 50 years (1955-2005) from 25 meteorological stations in grain production area of eastern Inner Mongolia.The results indicated that：（1）Nearly 50 years the regional temperature humidity matching pattern was changed，and the tendency on climate warming and drying were especially obvious in recent 20 years; （2）Precipitation was the key meteorological factor affecting crop yields while the lack of rainfall in spring or summer,and the high temperature in growing seasons were the main limitation factor to crop production; （3）Each crop had its own most sensitive factors. For instance，for wheat and millet was precipitation,while high temperature in summer for corn,and temperature difference in July to August and precipitation in April to May for potato.（4）The model calculated results indicated that the average maximum temperature or temperature difference increase of 1℃ in growing season could cause the meteorological yield decreasing by 102~192kg/ha for corn，by 87kg/ha for soybean，but increasing by 55.5kg/ha for potato production. In conclusion，the climate tendency of warming and drying could cause the decline of regional agricultural production.

Key words: Climate change, Crop yield, Response, Eastern Inner Mongolia