Abstract: Flotation efficiency has a significant impact on higher content of fine coal in coal separation.Flotation effect can be improved prominently by the addition of flotation reagents.We selected kerosene and diesel oil as collectors,sec-octyl alcohol and QPJ as frothers to measure the surface tension of coal slurry contained flotation reagents,and selected kerosene as collectors,sec-octyl alcohol as frothers to carry out the laboratory flotation experiments.With these tests we explored the influence of flotation reagents for coal slurry surface tension and flotation effect.The results show that there is a relatively close relationship between the surface tension of coal slurry and the flotation effect.With the increase of the dose of collecting agent or foaming agent,the surface tension of coal slurry reduces 10 mN/m while the recovery of combustibles increases 15%.The recovery of combustibles comes to the peak when the surface tension is the lowest.