A feeding device includes a support mechanism, a movable platform, a driving mechanism, a clutching mechanism, and two or more holding mechanisms. The movable platform is movably connected to the support mechanism, and loads feed trays stacked together. The driving mechanism drives the movable platform to move relative to the support mechanism. The holding mechanisms are fixed on the support mechanism, and switch from a first position to a second position. When the holding mechanisms are positioned in the first position, the holding mechanisms grasp one feed tray adjacent to a feed tray at a top of the feed trays, and the clutching mechanism clutches the feed tray at the top of the feed trays. When the holding mechanisms are positioned in the second position, the holding mechanisms separate from the feed trays.