A Unified Protocol (UniPro) device with self functional test includes a physical layer circuit and a UniPro interface. The physical layer circuit has a transmit (TX) port and a receive (RX) port, wherein the TX port and the RX port are connected to each other via a loopback link under a self-test mode. The UniPro interface generates an outgoing test pattern to the TX port, and checks an incoming test pattern received from the RX port under the self-test mode.