The present invention relates to an apparatus and a method for manufacturing metal foil by electroforming. Provided is a horizontal electroforming apparatus comprising: base plate supply means for continuously supplying flexible and conductive base plates to be provided as cathode electrodes in one horizontal direction; a horizontal cell including a conductor roll which contacts a widthwise edge portion of the base plate to transfer the base plate and supply current to the base plate, anode electrodes arranged at one side of the base plate or spaced apart from each other at both respective sides of the base plate, an electrolyte supply device for supplying an electrolyte containing metal ion through a horizontal path formed by the base plates and the anode electrodes, and current supply devices arranged at one side or both sides of the base plate to supply current to the conductor roll and to the anode electrodes so as to enable electroseparation of the metal ion; and delaminating means for delaminating, from the base plate, metal foil electrodeposited at one side or both sides of the base plate.