Abstract: To increase flotation efficiency of the scarce difficult-to-float coals,take four scarce coals from Zhaogezhuang in Hebei province,Xinxing in Heilongjiang province,Xuecheng in Shandong province and Malan in Shangxi province as examples,using the measures of optical microscopy,scanning electron microscope,X-ray diffraction and fluorescence spectrum analysis analyzed the physicochemical properties of scarce difficult-to-float coals.The results show that in maceral of scarcity coal samples,the content of vitrinite and inertinite is bigger;the shape of pores on coal surface presents ring,pitting and stripe,in which cracks enriched heterogeneous fine mud;the coals embedded with minerals of kaolinite,calcite,quartz,pyrite that difficult to floating;coals contains a lot of paraffin,alcohol compounds and kaolin,the chemical composition of mineral components mainly is SiO₂,Al₂O₃ and Fe₂O₃.