In a defroster structure, a first guide member is provided further toward a vehicle front side than a front-rear partitioning wall and at a vehicle transverse direction outer side, at an interior of a blow-out port. A second guide member is provided further toward a vehicle rear side than the front-rear partitioning wall and at the vehicle transverse direction outer side, at the interior of the blow-out port. The first guide member and the second guide member respectively extend toward the vehicle transverse direction outer side from a vehicle lower side toward a vehicle upper side.