To improve the efficiency of the stirring and filtering of an electroforming soln., to make easily executable an electroforming in a matrix with a shape of strong and complicated ruggedness at a high speed, moreover to facilitate partial electroforming and to reduce the waste of metal such as nickel.

As to the electroforming method and device, in the air, with an object 19 to be electroformed as a cathode, and an insoluble electrode 20 of platinum, gold or the like in an electroforming gun as an anode, an electroforming soln. in which liq. temp. and liq. compsn. are controlled and freed of impurities is pressurized with a pump, and, in a state of continuous liq. flowing from the nozzle 22 of the electroforming gun, while DC electric current is flowed, it is toward the object to be electroformed and is electroformed. The electroforming device is provided with a cathode composed of the object to be electroformed, an anode composed of an insoluble electrode 20 of platinum, gold or the like incorporated into an electroforming gun and a pump 23 executing jetting the electroforming soln. freed of impurities, from the nozzle of the electroforming gun toward the cathode in a state of continuous liq. flow while DC electric current is flowed.