PURPOSE: To maintain a heating device at a fixed temperature so as to manufacture a band wire of fixed quality by using an intermittently heated preheating device, and driving a band wire manufacturing device with a time difference kept between heating process and movement of wires.

CONSTITUTION: A preheating device 5 is provided which serves as a preheating means for heating to a predetermined temperature a plurality of insulated core wires 3 arranged in parallel in their longitudinal direction and intermittently drawn by a drawer 3 end a control device 11 is provided which serves as an action controlling means for actuating the preheating device 5 before actuation of the drawer 3 is started, and lowering actuation of the preheating device 5 before actuation of the drawer 3 is stopped. Thus a band wire manufacturing device is so controlled that there is a time difference between movement and heating of each insulated core wire 1 in order for the preheating device 5 to heat each insulated core wire 1 at a fixed temperature. Thereby the insulated core wires 1 preheated at a fixed temperature are thermally fused to each other under fixed conditions by pressure contact method so as to make the quality of a band wire constant.