A communication apparatus is connected to a network and identifies a flow of a frame input thereto and outputs the frame to a port. The communication apparatus includes: a flow identifying unit that obtains a flow identifier of the flow to which the frame belongs, and that obtains, based on the flow identifier, a hash rule corresponding to the flow identifier; a transfer destination controller that obtains by calculation a hash value of the frame by making use of the hash rule obtained by the flow identifying unit and that decides on an output port for the frame based on combination of the flow identifier and the hash value; and a frame output unit that outputs the frame to the output port decided by the transfer destination controller.