China has a vast territory, and the cultures in the South and the North are very different.　As an important part of Chinese culture - diet, There is something in common between the North and the South, and there are also big differences. The commonality between the North and South food culture lies in the traditional Chinese philosophy. Philosophy of "Yin Yang and Five Elements", philosophy of "the Integrity of Man and Nature", philosophy of "Beauty of Neutralization and Harmony", philosophy of "Dietary Therapy"etc. The difference lies in"south rice and north flour","south sweet and north salty", different cooking methods and eating methods, and different wine culture and tea culture. Then this article explores the natural environmental causes and human environmental causes of dietary differences between the North and the South. Finally, For various reasons, the difference between the North and South diets is gradually decreasing. North and South food culture blends with each other, but each region maintains its own characteristics, China's North and South food culture will always maintain a balance between collision and blending, and has continued and developed.