A detailed comparison was done between the data about the F in coals pub-lished at home and abroad, and associated with the special situation in China. An intro-duction also was made to illuminate the forming, occurrence and accumulation of the F in coals and its potential hazard to human and environment. Analytical data of coal samples were referred to study the great difference of the F content between coals and gangue.The results show that the average value of the F in the coal samples collected in different coalfields of China is 304×10-6, while that of gangue samples is surprisingly 1 319×10-6,especially the F content of coal ash from Bangmai in Yunnan Province reaches 4 800x10-6.It has been proved in many provinces of China that burning the coal and clay mixture can produce F contamination.