A transfer device for coupling a priority signal and a standard signal and transferring the signal includes a reception unit that receives a plurality of signals transmitted from a device connected to an opposite side of a transfer route, a separation unit that separates the signal into the priority signal and the standard signal, a signal defragmentation unit that defragments the plurality of standard signals, a multiplexing unit that multiplexes each of the priority signal and the standard signal, a priority control unit that determines a transfer order of the signals, a header information copy unit that copy header information of the standard signal, a transmission unit that transmits the signal to a device connected to the transfer route, an interrupt transfer processing unit that perform an interruption process when the priority signal arrives during the transfer of the standard signal, a signal fragmentation unit that fragments the standard signal, a header information assignment unit that assigns the header information to the standard signal, and a transmission delaying unit that delays the transfer of the standard signal until the priority signal has been transferred.