The invention relates to an insulated tubular bus main insulation material thermal aging performance test system. The system comprises a data processing and analysis module, and a dielectric loss test module, a power-frequency breakdown field intensity test module and a thermal extension test module which are connected with the data processing and analysis module. The dielectric loss test module, the power-frequency breakdown field intensity test module and the thermal extension test module each include an external experiment box body. A constant-temperature and constant-humidity box is placed in each experiment box body. A computer input interface connected with the data processing and analysis module is placed in each constant-temperature and constant-humidity box. The system is equipped with analysis software, and has the functions of test data acquisition and data processing and analysis. The system can judge the thermal aging condition and thermal aging degree of a material accurately, and provide rich decision-making reference information for technical personnel.