Abstract: To solve the problems of wider size fraction of fine feed,high ash content fine slimes are entrained into overflow so that coursed high ash content of clean coal during liquid-solid fluidized bed separation,which seriously effected the liquid-solid fluidized bed separation result and clean coal quality,presents combined process of liquid-solid classification and coal cleaning with liquid-solid fluidized bed,in which the coarse and fine slim classified with liquid-solid fluidized bed and the overflow separated with flotation,the underflow separated with second liquid-solid fluidized bed,which process can precisely separate both coarse and fine slimes.The application results in Liangbei coal preparation plant show that the combined process of liquid-solid classification and coal cleaning with liquid-solid fluidized bed obtained better result,the high ash content fine slimes decreased by 80.32% in feed,and ash content in coarse clean coal decreased by 2.43%.