Abstract: According to relative investigations and statistical information of grain production in more than fifty years in Shanxi province, we analysis the change tendencies and influence factors of grain yield and crop structure in Shanxi province by using the combination of static analysis and dynamic analysis and the method of combination of qualitative analysis and quantitative analysis. The result shows: the total output and per unit area yield of grain tend to a increasing tendency in fluctuating in Shanxi province since the foundation of People’s Republic of China; Great changes have taken place in grain structure. The increase of grain total output mainly owes to the increase of per unit area yield of grain. The increase of the per unit area yield of the maize greatly influence the increase of average per unit area yield of grain among them, the second is wheat. Then it puts forward the following suggestions: the increase of the per unit area yield of grain depends on improving of agriculture production condition and agriculture science level; it can stabilize the area of wheat sowing, and to satisfy people's demands for grain ration consumption of wheat; Maize, as a high-efficient crop of high yield for the grain and feed, the cultivated area in the future should be further expanded.