A humidifier including a water container, a dividing plate and an airway structure is provided. The water container has a top and a bottom opposite to the top. The top of the water container has a first air outlet. The dividing plate is disposed in the water container and dividing an internal space of the water container into a first space and a second space. The first space is defined between the bottom and the dividing plate and the second space is defined between the dividing plate and the top. The airway structure is disposed in the second space and having a certain distance to the top. The airway structure has an air inlet and a second air outlet. The air inlet of the airway structure is connected to a sidewall of the water container and the second air outlet is connected to the dividing plate.
