To decrease as much residual stress remained in a ring of a chain as possible by forming a ring of a chain through bending both the ends of a wire in a U-shape applying at various positions to decrease the number of composing parts of the device to a great extent by simplifying an operating mechanism required for forming a ring of the chain and to enable mass production of chain of various kinds of standards, which is simple in handling, excellent in maintainability and high in reliability.

At a primary working position (a) set in front of a mouth piece 1, a primary bending mechanism 2 is provided to bend one end of a wire A into a U-shape. At an end part of a fixed table 7 installed under the primary bending mechanism a secondary working position (b) is set. At the secondary working position (b), a secondary banding mechanism 10 is provided which bends the other end of a wire A1 bent by the primary bending mechanism into a U-shape to form a ring of the chain A2. The wire bent by the primary bending mechanism is transferred to the location of the secondery bending, is bent by the secondary bending mechanism, and then is combined with a ring of the chain A2 of the chain on standby in a hanging state at the secondary working location.