In order to test the performances of working frequency, signal power spectral density,anti-jamming capability,noise immunity and anti-impedance changes for low voltage broadband power line carrier communication unit under the requirements of Q/GDW 1379.4-2013 technical specification and give data reference,scheme basis to grid company to construct remote metering system for broadband power line carrier.A point to point communication performance testing platform is formed according to the characteristics of broadband power-line carrier.Three cascade power filter with double SMA terminals are adopted which can insulate the influence on the communication performance for broadband carrier communication unit caused by harmonic,pulse signal and power-line background noise.As a consequence,the testing platform mentioned above can fully simulate the low voltage power line channel,restitute the operational state of site metering pilot and assess the actual usage of carrier communication unit.Experimental data certifies that the experiment environment of the testing platform constructed is pure,which can attenuate signal within the bandwidth of 1~30MHz up to 93dB so as to ensure that the tested performance data of broadband carrier communication unit is stable and reliable.