Abstract: The experiment was carried out by using the laboratory fluidized bed, which is the research object of the coal coarse with -2.0+0.5 mm. The optimized Design of low-density, low-density coal pellets was carried out by design-expert 8.0 software, and the optimal solution for the flotation of different particle size particles was carried out. And the full graded full level density fluidized bed flotation, the results show that, when the rising flow velocity of 1.39 cm/s, airflow apparent velocity of 0.104 cm/s, collector reagent dosage of 9.0 μL/L, ash is 12.23%, the tailing ash can be divided into 54.94%, yield is 45.06%.