Jilin province is one of the most important commodity grain base in China,so researches on the change of grain yield per hectare in Jilin province is of significance for ensuring grain supply.Using data of production conditions for agriculture from 1984 to 2007 as independent variables,their impacts on grain yield per hectare were analyzed in the paper using linear regression.The results showed that grain yield per hectare could be explained on 87.9% degree by irrigated area,consumption of chemical fertilizers,power of agricultural machinery,area affected by disasters,etc.Among them,irrigated area,consumption of chemical fertilizers,decreasing area affected by disasters have positive function to grain yield;however,grain output decreased with increasing power of agricultural machinery,so we need adopt related countermeasures.