Broadband power line carrier communication system is a hot research topic in the current smart grid communication system. The system performance test equipment and corresponding standards for broadband power line carrier communication under laboratory environment have still not been solved. This paper proposed the architecture, design principle and function of automatic carrier channel simulation test system for intelligent distribution network. In order to verify the feasibility and flexibility of our proposed system, the simulated channel characteristics under different distribution parameters are measured and analyzed. The test items and corresponding evaluation methods are proposed under simulated channel. From the implementation results, it has been proved that our proposed system can provide a convenient and effective solution for broadband power line carrier communication system performance test.