Coal mining method and device for working face and coal mining system for coal mine

The invention provides a coal mining method and device for a working face and a coal mining system for a coal mine. The method comprises the steps that the position of a hydraulic support is obtained, the hydraulic support is located in a connection roadway, the connection roadway is used for communicating two air return crossheads, and the air return crossheads are air return roadways of the coal face; a target area is obtained, the target area at least comprises the area capable of being cut by a coal mining machine, and the coal mining machine is located in the connection roadway; and the coal mining machine is controlled to cut at the position of the hydraulic support, so that the hydraulic support supports the connection roadway when the coal mining machine cuts, and coal mining is carried out on the target area. According to the scheme, the open-off cut is not installed in the working face, namely, the open-off cut is removed, the hydraulic support is directly installed in the connection roadway, the to