An apparatus for producing a metallic ribbon includes a cooling roll (1), a melt nozzle (2), and an air-cutoffunit (60) provided to cover at least a portion of the periphery of the cooling roll (1) and at least the melt blowout end ofthe melt nozzle (2), for preventing an inflow of air due to rotation of the cooling roll. The air-cutoff unit (60) has a roll top air-cutoff plate provided above the cooling roll to extend from the front side to the rear side in the rotation direction of the cooling roll in such a manner that it approaches the cooling surface in the direction opposite to the rotation direction of the cooling roll. The melt blowout end of the melt nozzle (2) is arranged to pass through a nozzle mounting hole provided in the roll top air-cutoff plate and face the cooling surface of the cooling roll. A method of producing a metallic ribbon uses the apparatus.