A drying device comprising: an air blowing portion (20, 81) for blowing pressurized air so as to dry a surface to be dried by a jet of pressurized air whose abutment area to the surface to be dried is narrower than the surface to be dried; and a moving unit for moving the air blowing portion (20, 81) while the jet is being blown such that the jet blown from the air blowing portion sequentially sweeps a substantially entire surface of the surface to be dried, wherein the moving unit includes a first moving device for moving the air blowing portion (20, 81) in a state in which a blowing direction of the jet is being maintained so as to form a predetermined angle with respect to a moving direction of the air blowing portion (20, 81) and a second moving device for moving the air blowing portion in a direction different from that of the moving direction, wherein the moving unit includes cyclic movement for cyclically reciprocating the air blowing portion (20, 81) in a fixed direction and gradual movement for moving the cyclic movement in a predetermined direction, and sweeps the abutment area of the jet over the substantially entire surface of the surface to be dried, and characterised in that there are provided a first step in which a direction of the cyclic movement of the moving unit is set as a leftward and rightward direction of the surface to be dried, and the gradual movement is effected from a predetermined position forward of a center of the surface to be dried toward a substantial center thereof, and a second step in which the gradual movement is effected from a predetermined position backward of the center of the surface to be dried toward the substantial center thereof, and the first step and the second step are executed, or in that there are provided a first step in which a direction of the cyclic movement of the moving unit is set as a forward and backward direction of the surface to be dried, and the gradual movement is effected from a predetermined position on one side either leftward or rightward of a center of the surface to be dried toward a substantial center thereof, and a second step in which the gradual movement is effected from a predetermined position on another side leftward or rightward of the center of the surface to be dried toward the substantial center thereof, and the first step and the second step are executed. an air blowing portion (20, 81) for blowing pressurized air so as to dry a surface to be dried by a jet of pressurized air whose abutment area to the surface to be dried is narrower than the surface to be dried; and a moving unit for moving the air blowing portion (20, 81) while the jet is being blown such that the jet blown from the air blowing portion sequentially sweeps a substantially entire surface of the surface to be dried, wherein the moving unit includes a first moving device for moving the air blowing portion (20, 81) in a state in which a blowing direction of the jet is being maintained so as to form a predetermined angle with respect to a moving direction of the air blowing portion (20, 81) and a second moving device for moving the air blowing portion in a direction different from that of the moving direction, wherein the moving unit includes cyclic movement for cyclically reciprocating the air blowing portion (20, 81) in a fixed direction and gradual movement for moving the cyclic movement in a predetermined direction, and sweeps the abutment area of the jet over the substantially entire surface of the surface to be dried, and characterised in that there are provided a first step in which a direction of the cyclic movement of the moving unit is set as a leftward and rightward direction of the surface to be dried, and the gradual movement is effected from a predetermined position forward of a center of the surface to be dried toward a substantial center thereof, and a second step in which the gradual movement is effected from a predetermined position backward of the center of the surface to be dried toward the substantial center thereof, and the first step and the second step are executed, or in that there are provided a first step in which a direction of the cyclic movement of the moving unit is set as a forward and backward direction of the surface to be dried, and the gradual movement is effected from a predetermined position on one side either leftward or rightward of a center of the surface to be dried toward a substantial center thereof, and a second step in which the gradual movement is effected from a predetermined position on another side leftward or rightward of the center of the surface to be dried toward the substantial center thereof, and the first step and the second step are executed.