In order to overcome the impact of different types of noises in the power line communication system (PLC), moreover, improve the low signal to noise ratio (SNR) situation and the reliability of the communication system, this paper presents a noise mitigation method based on time-frequency peak filtering (TFPF). TFPF is the technique that encodes the signal as instantaneous frequency (IF) of an analytic signal by frequency modulated. Then, the signal is recovered by getting peak of WVD of analytic signal according to frequency. For the nonlinearity of the power line communication system data, the WVD added window function is utilized to execute TFPF. Numerical experiments have shown that the TFPF method can effectively eliminate the power line communication system noise, reduce the Bit Error Rate (BER) and improve the quality of communication system.