Disclosed is a bidirectional packet transfer fail-over switch for serial communication. The bidirectional packet transfer fail-over switch for serial communication includes a memory configured to divide packet data, which is transmitted or received for bidirectional communication between a plurality of communication devices, in units of certain data, and store the divided data, and a control unit configured to receive a trigger signal, indicating whether the packet data is received, from the memory, determine a priority according to an order where the packet data is received, and transmit the packet data to another communication device.