Abstract: Endemic fluorosis is caused by excess fluorine of natural environment entering human body through food chain.This is one of the most extensive epidemic regional diseases in China. The distribution of this disease has obvious district characteristics.The area of this disease in China may be divided into three regional zones.(1)The ariplain in the north of China,it’s outstanding character is the dry climate which causes fluorine accumulation in Ouaternary deposits;thus,the drinking water with high content of fluorine forms the cause of this disease;(2)the Yunnan-Guizhou Plateau with a very high content of fluorinein rocks and soils,thus,the crop food with high content of fluorine forms the cause of this disease;(3)the Southeast Hills,the hot springs with high content of fluorine lead to this disease. In general,the disease has certain particular physical geographical characteristies.The landforms in the disease district are of low-lying areas benefitting fluorine accumulation there.Saline-alkli soil is extensively found in the disease district,there are a lot of Soda,it benefits to increase chemical activity of fluorine. Plant types are halophiles and calciphile. The fluorine entering human body from environment is firstly through drinking water;secondly the fluorine in soil enters human body through crop food.The fluorine in air enters human body mainly through crop leaves.The prevention and cure of fluorosis depenp mainly on reforming the environmental natural accumulating fluorine,and breaking up the high fluorine food chain(mainly drinking water)entering human body.