Abstract: Aiming at the problems of scraper conveyor in fully mechanized working face of steeply inclined coal seam with artificial extension and shrinkage device, such as difficult operation, easy decline, large safety hazards. A kind of automatic extension and shrinkage device is proposed, it is introduced in detail that the device structure, work principle and the actual application effect of Lushuidong Coal Mine in Sichuan Coal Group, which provides a certain reference for the scraper conveyor design in fully mechanized working face of steeply inclined coal seam.