A humidification device includes: an adsorber having an adsorbent that adsorbs and desorbs moisture; an adsorption case that forms an accommodating space to accommodate the adsorber; a first introduction portion that introduces cooled air produced by a cooling portion into the adsorption case; a second introduction portion that introduces heated air produced by the heating portion into the adsorption case; and a humidification-side guiding portion that guides humidification air humidified by the moisture desorbed within the adsorption case, to the vehicle interior. The first introduction portion is connected to a bottom surface portion of the air-conditioning case on the air-flow downstream side of the cooling portion in the air-conditioning case.