Abstract: A bolt feeder is for supplying a bolt to a resistance welding machine that performs resistance-welding of a workpiece and the bolt using a lower electrode. The bolt feeder comprises a holding unit configured to receive the bolt fed by a bolt feeding unit with a head located above a shaft, a moving unit configured to move the holding unit, and a pusher member configured to protrude from and retract into a tip end of the upper electrode. The bolt includes a projection on a top surface of the head which is opposite to a surface provided with the shaft. The lower electrode includes an insertion hole into which the shaft is inserted. The shaft is inserted into the insertion hole by the pusher member protruding from the tip end of the upper electrode and pushes an area of the top surface where the projection is absent.