Abstract: Selective agglomeration technology was used to deal with difficult-to-float coal slime. Liberation degree of difficult-to-float coal slime was first determined, and the coal slime-0.074mm fineness account for 86.85％, then explorative test were carried on of different variants changes of stirring speed, stirring time, dispersant dosage and non-polar oil consumption. The test result indicates that the method is feasible. The optimum conditions of selective agglomeration technology were XHF-D high-speed mixing speed and mixing time respectively 8000r/min, 20min, and Sodium hexametaphosphate dosage for 1500g/t, and kerosene for 790g/t. under the condition concentrate yield was 58.72%, concentrate ash content was 10.69%, and coal combustible components recovery was 68.42%.