Abstract: There is provided a rear cushion device to be mounted between a vehicle main body and a rear suspension arm of a saddle ridden-type vehicle and including a spring and a damper. The damper includes: a cylinder; a piston; a rod; a cylinder-side mounting part; and a rod-side mounting part. The rod-side mounting part includes: a cylindrical inner member fixed to the other axial end side of the rod coaxially with the rod, and having an outer peripheral surface on which a screw is formed; and an outer member mounted to an outer peripheral side of the inner member. The outer member includes: a tubular part having an inner peripheral surface on which a screw to be screwed with the screw of the inner member is formed; and a coupling part for coupling the outer member to the vehicle main body or the rear suspension arm.