To provide a humidification unit capable of keeping a sanitary state in a tank, even when not in use for a long period of time, and to provide a washstand with the same.

The humidification unit 1 includes: a humidifier 2 for atomization and humidification of the water in a tank 20; a water supply valve 3 connected with a water supply pipe (30) for supplying water to the tank; a drain valve 4 connected with a drain pipe (40) for draining the water stored in the tank; and a controller for controlling the water supply valve and the opening and closing of the drain valve. When the humidifier is not turned from an off-state to an on-state for more than a fixed time, the controller controls the replacement of water in the tank.