The invention provides a communication device and a communication system. The communication device comprises a processor connected with an encoding and decoding module, the encoding and decoding module connected with a first bus interface and a second bus interface, the first bus interface connected with any transmission line of an external bus, and the second bus interface connected with anothertransmission line of the bus, wherein the processor is used for sending to-be-sent information to the encoding and decoding module when the to-be-sent information needs to be sent and receiving the to-be-sent information sent from the encoding and decoding module, the encoding and decoding module is used for encoding the to-be-sent information when the to-be-sent information is received and transmitting encoded to-be-sent information to the bus through the first bus interface and the second bus interface, and decoding the to-be-sent information when the to-be-sent information transmitted fromthe bus is received and sending decoded to-be-sent information to the processor. By adopting the communication device and the communication system, communication faults can be decreased.