Abstract: A wire harness manufacturing apparatus includes plural manufacturing lines for respectively manufacturing plural sub-wire harnesses as constituents of a wire harness to be produced, each of the manufacturing lines including plural constituent devices arranged in manufacturing order of each sub-wire harness. Plural line control devices are provided for controlling operational processes of the manufacturing lines respectively. Each of the line control devices is connected with the constituent devices of each of the manufacturing lines through a signal transmitting circuit. At least one system control device is adapted so as to construct a signal transmitting network together with the line control devices, for controlling manufacturing loads among the plural manufacturing lines.