Abstract: The climatic suitable index for crops under different climatic years are analysed by using the unit production of five main crops in Xinmin county of Liaoning Province.Then the schemes of crop structure adjustment for different climatic years are put formard basedon linear programming.This provides the basis for reducing agricultural disasters and keeping high and steady agricultural production.Under the adjusted crop structure the total grain output and value would be increased 8.85 percent and 8.17 percent,respectively,in bumper years,in normal years the increase wouldbe 20.49 percent and 19.86 percent and in lean years the increase would be 20.15 percent and 19.30 percent.If the type of the year is not concerned,the average increase rate would be 8.86 percent and 7.79 percent,respectively.