Under the background of "The Belt and Road" in the new era, the food trade cooperation between China and countries along the Belt and Road is also facing a new stage. At the same time, China's food supply and demand gap is gradually increasing. In this background, this article analyzed our country along with the national food trade complementary degree, and based on the gravity model, on the basis of introduction of population, food production,trade freedom, whether to have a common border, whether both belong to the Shanghai cooperation organization,whether both belong to the WTO may affect the import trade of variables such as regression analysis, and use the model to estimate growth space. It is found that the degree of grain trade complementarity between China and countries along the line is different, but it is mainly inter industry trade. Under the existing trade model, there is still considerable room for import improvement between China and most countries along the line. According to the above analysis results, the paper points out the corresponding measures and strategic suggestions at the end.