Abstract: An improved cassette loading/unloading device for use with magnetic tape machines is disclosed. It contains a connection member, which includes a first stopper portion extending from a drive plate toward a sliding plate; a second stopper portion mounted on a rear side of the first stopper portion; a connection sheet extending from the sliding plate into a space between the first and second stopper portions; a connection pin penetrating through the first, and second stopper portions and the connection sheet along the path of insertion of the cassette into the magnetic tape unit for relative sliding with the connection sheet; and a buffer spring provided on the connection pin between the second stopper portion and the connection sheet for buffering an impact force when the drive plate pushes the sliding plate.