A file suspension device for holding hanging file folders in a box. The file suspension device includes a frame. The frame has an elongate first rod, an elongate second rod, an elongate third rod and an elongate fourth rod. A fastening structure is provided on at least two of the rods for removably fastening each of the at least two rods on the top edge of one of the walls of the box. The fastening structure pinches an upper portion of the wall when the fastening structure is fastened to the wall for retaining an associated rod on the wall.