A water tank for a sweeper and a sweeper including the same are provided. The water tank for the sweeper includes: a water tank lower cover, a bottom of which is provided with a containing groove; a water tank upper cover, which is connected with the water tank lower cover; a water tank release button arranged at the containing groove; and a reset member, a first end of which is coupled to the water tank release button and a second end is coupled to the water tank lower cover.