A hot air drying device (2) allowing a conveyor (4) to pass from one end side to the other end side in longitudinal direction and a noodle line stored in the conveyor and transferred from a previous process to move through the inside of the device at a specified speed, comprising a plurality of longitudinally divided drying chambers (D1, D2, D3, D4, D5, ...), each drying chamber further comprising a heater for heating the indoor air to a set temperature, a blowing fan for blowing the produced heated air, as hot air, to an indoor underside where the conveyor is disposed, an air leading part for leading the hot air blown from the blowing fan to the lateral upper or lower side of the conveyor, and a flow straightening part (12) for straightening the air flow so that the hot air flowing through the upper or lower side of the conveyor (4) is blown down or blown up toward the conveyor.