Abstract: In this paper,a series of flotation test to flotation feeding from Fenxi Zijin coal preparation plant had been conducted using XFD_Ⅳ flotation machine,investigated the influences of the aeration rate,impeller speed and the ratio and dosage of agents on the flotation index.The test results show that when the aeration rate is 150 L/h,the impeller speed is 1 800 r/min,the ratio of collecting agent and foaming agent is 4 to 1 and their dosage is 1 200 g/t and 300 g/t respectively,better flotation result can be obtained.