The present invention is to provide a PLC device having noise detecting and filtering functions, which includes a power receiving port having one end connected to a power supply unit for receiving a power signal and a network signal; a noise filtering circuit having one end connected to the other end of the power receiving port for filtering noise of the power signal passing therethrough; a power output port connected between the other end of the noise filtering circuit and a load; a noise detecting circuit having two ends connected to a line between the first filtering unit and power receiving port and a line between the first filtering unit and power output port, respectively; and a processing unit connected to a line between the first filtering unit and power receiving port for receiving the network signal from the noise detecting circuit and transmitting the same to a network apparatus.