A work processing apparatus upwardly turns a wrist of a vertical articulated robot to retract a hand that is holding a work to a position where the hand and work do not interfere with a press brake. In this state, an engaging projection arranged at a front end of an upper arm or at the wrist is inserted into an engaging hole of a lower die of the press brake and the vertical articulated robot is operated to move the lower die along a groove of a die holder.