The utility model discloses a portable moisture regain device of tobacco leaf in roast room, including the water spray component, the water spray component is including water spray component board, be provided with the spray pipe on the water spray component board, the spray pipe is provided with a plurality of shower nozzle, two bisymmetry settings in the shower nozzle, comprising a water tank, be provided with the heating pipe in the water tank, the water tank intercommunication has first filter and second filter, makes the moisture regain time contraction by 4 hours, can go out the cigarette packing, uses the utility model discloses the moisture regain back, the moisture of tobacco leaf is 16.5%~17.5%.