A method for producing a forged crankshaft including journals serving as a center of rotation, pins decentered from the journals, and crank arms connecting the journals and the pins, wherein the forged crankshaft further includes counterweights integrated with all or some of the crank arms, the method comprising: a rough forging step of performing die forging to obtain a rough forged blank with flash having a crankshaft shape; and a finish forging step of applying die forging by use of a first pair of dies to the rough forged blank to obtain a finish forged blank with flash, wherein: the rough forged blank includes rough journals (J'), rough pins (P'), rough crank arms (A'), and rough counterweights, which correspond to the journals, the pins, the crank arms, and the counterweights of the forged crankshaft, respectively; at least one of the rough crank arms (A') has, in a region near an adjacent one of the rough pins (P'), a first excess portion (Aaa, Aba) protruding from an outer periphery of a side portion (Aa', Ab') of the rough crank arm (A'); and during the die forging in the finish forging step, the first excess portion (Aaa, Aba) is deformed by the first pair of dies to bulge toward an adjacent one of the rough journals (J'), while: (a) a second die (20, 21, 22) is in contact with a rough-journal-facing surface of the rough crank arm (A') at a portion between the first excess portion (Aaa, Aba) and the flash; and/or (b) a holder is holding a lower surface of the flash, and the holder moves along with a movement of the first pair of dies while keeping holding the lower surface of the flash. a rough forging step of performing die forging to obtain a rough forged blank with flash having a crankshaft shape; and a finish forging step of applying die forging by use of a first pair of dies to the rough forged blank to obtain a finish forged blank with flash, wherein: the rough forged blank includes rough journals (J'), rough pins (P'), rough crank arms (A'), and rough counterweights, which correspond to the journals, the pins, the crank arms, and the counterweights of the forged crankshaft, respectively; at least one of the rough crank arms (A') has, in a region near an adjacent one of the rough pins (P'), a first excess portion (Aaa, Aba) protruding from an outer periphery of a side portion (Aa', Ab') of the rough crank arm (A'); and during the die forging in the finish forging step, the first excess portion (Aaa, Aba) is deformed by the first pair of dies to bulge toward an adjacent one of the rough journals (J'), while: (a) a second die (20, 21, 22) is in contact with a rough-journal-facing surface of the rough crank arm (A') at a portion between the first excess portion (Aaa, Aba) and the flash; and/or (b) a holder is holding a lower surface of the flash, and the holder moves along with a movement of the first pair of dies while keeping holding the lower surface of the flash. the rough forged blank includes rough journals (J'), rough pins (P'), rough crank arms (A'), and rough counterweights, which correspond to the journals, the pins, the crank arms, and the counterweights of the forged crankshaft, respectively; at least one of the rough crank arms (A') has, in a region near an adjacent one of the rough pins (P'), a first excess portion (Aaa, Aba) protruding from an outer periphery of a side portion (Aa', Ab') of the rough crank arm (A'); and during the die forging in the finish forging step, the first excess portion (Aaa, Aba) is deformed by the first pair of dies to bulge toward an adjacent one of the rough journals (J'), while: (a) a second die (20, 21, 22) is in contact with a rough-journal-facing surface of the rough crank arm (A') at a portion between the first excess portion (Aaa, Aba) and the flash; and/or (b) a holder is holding a lower surface of the flash, and the holder moves along with a movement of the first pair of dies while keeping holding the lower surface of the flash. (a) a second die (20, 21, 22) is in contact with a rough-journal-facing surface of the rough crank arm (A') at a portion between the first excess portion (Aaa, Aba) and the flash; and/or (b) a holder is holding a lower surface of the flash, and the holder moves along with a movement of the first pair of dies while keeping holding the lower surface of the flash.