Abstract: For reducing the ash of Fuyuan bituminous coal of Yunnan Province, a study is made on such factors as feed size, pulp density, flotation process flowsheet, and dosages of collector, frother and inhibitor. Study result shows that for treating a feed with the < 0.075 mm size accounting for 80% by applying the one roughing plus two cleaning processes at a feed pulp density of 100 g/L and dosages of collector (diesel oil), frother (terpineol) and inhibitor (sodium silicate) of respectively 300 g/t, 100 g/t and 2 000 g/t, a concentrate product with a yield of 42.16% and an ash as low as 3.11% can be obtained.