The invention relates to the technical field of tidal power generation, and particularly discloses a tidal power generation device. The tidal power generation device comprises a generator set, a reservoir and a lever system, wherein the lever system comprises a controller, a base module and a lever module, the lever module comprises a lever and a supporting seat, a rotating shaft is arranged between the lever and the supporting seat, the lever is rotatably mounted on the supporting seat through the rotating shaft, and the supporting seat is arranged on the base module; a first containing cavity and a second containing cavity are formed in the two ends of the lever, and the volume of the first containing cavity is larger than that of the second containing cavity; and the base module is further provided with a clamping module, and the clamping module clamps or loosens the lever under the action of the controller. According to the tidal power generation device, seawater is used for powergeneration, fuel is not needed in the power generation process, pollution is avoided, and the modern environment-friendly concept is met; meanwhile, the influence of season or climate factors on the generating capacity is avoided, and the use stability is high; and the tidal power generation device is suitable for sea areas with low sea level and can be applied and developed on a large scale.