The invention relates to a generation device, more specifically a tidal energy generation device, comprising an enclosure mechanism, a tidal energy switching mechanism and a mechanical energy switching mechanism; the device can transform the tidal energy into the mechanical energy, transform the mechanical energy into electric energy and change the height of a tidal energy pushing plate accordingto the quantity of the tidal energy so as to prevent water from entering the device; the device can run safely, and can be more convenient to maintain, lift and move; the tidal energy switching mechanism is arranged in the enclosure mechanism; the connection type of the tidal switching mechanism and the enclosure mechanism is partial welding and partial clearance fit; the mechanical energy switching mechanism is arranged in the enclosure mechanism; and the connection type of the mechanical energy switching mechanism and the enclosure mechanism is partial bearing connection and partial welding.