Abstract: Following the launch of the initiative for switching to the new mode of green coal production, the coal mining - cleaning - underground backfilling integrated approach is of vital importance for reducing the volume of gangue hoisted up to surface, avoiding pollution caused by stockpiling of refuse, and enhancing recovery of coal resource, and it has become an important technological route for green development of coal industry. The paper presents a brief outline of current state of underground coal separation operation, an analysis of the significance and characteristics of such operations, as well as a comparison of the advantages and disadvantages of the technologies currently available. The work made in the paper can serve as a reference for the selection of the technological route for the development of underground coal separation projects in the future.