[PROBLEMS] To provide a wire feeder in which occurrence of slacking of the wire is eliminated by preventing inertial rotation of a wire bobbin. [MEANS FOR SOLVING PROBLEMS] The wire feeder for feeding a wire from a bobbin around which the wire is wound. The wire feeder comprises a rotary portion rotatable integrally with the bobbin while holding the bobbin; a base portion for supporting the rotary portion in a rotatable state; a metal flat plate fixed integrally to the rotary portion; and at least one magnet arranged at a position facing the major surface of the metal flat plate. The metal flat plate is fixed to the rotary portion such that the direction normal to its major surface is aligned with the axis of rotation of the rotary portion, and the wire is prevented from slacking by restraining inertial rotation of the rotary portion and the bobbin through electromagnetic induction occurring between the metal flat plate and the magnet.
