Abstract: The paper discussed the fine coal quality characteristics from coal preparation plant.Based on results of air-flow rate，we could find this coal sample was a hard flotation fine coal.We could not gain the low ash clean coal buy convention flotation process.The main reason which caused the high ash of clean coal was that low degree of mineral liberation and pollution of fine slit based on the results of particle size and float and sink test about flotation clean coal.Through the flowsheet that raw coal screen classification and grinding-flotation with coarse fraction，the ash of clean coal could be effective reduced.