To heighten processing speed in an input/output control unit for controlling data input/output between a processor device and an input/output device.

This control unit 100 has the processor devices 2, 2a and the input/output devices 3, 3a, 3b. Each processor device has a plurality of processors 4-7 and this input/output control unit 1. The input/output unit has output control elements 23, 24 having input ports from the plurality of processors and one output port respectively, and input control elements 25, 26 having ports for outputting to the processors and one input port respectively. Each input/output device has an input element 13, an output element 12, and an input/output data transfer device 14 for outputting data from the output control element to the output element, and outputting data inputted from the input element to the input control element. The output control elements and the input control elements are each connected by 1 to 1 to one of the input ports and the output ports of the input/output data transfer device means.