The invention discloses a fixing device for metal part manufacturing. The fixing device comprises a crate, a motor is fixedly mounted in the middle of the interior of the crate, and a motor support ismounted on the periphery of the motor. A driving shaft is mounted on the side, close to a work table, of the motor, a first gear is fixedly mounted on the driving shaft, and the two sides of the first gear are engaged with second gears matched with the first gear. Transmission shafts are fixedly mounted in the middles of the second gears, the sides, away from the motor, of the second gears are provided with gear belts matched with the second gears, and the gear belts and crawler belts mounted in the gear belts are fixedly connected. Movable shafts are movably mounted on the sides, close to the work table, of the crawler belts, fixing plates are movably mounted on the movable shafts, and infrared scanners and anti-sliding plates are fixedly mounted on the portions, close to the work table,of the fixing plates. The anti-sliding plates are mounted above the infrared scanners, and bases are mounted at the four corners of the lower portion of the crate.