The invention provides a thermal-vibration combined aging testing apparatus for an XLPE insulated sample section. The apparatus comprises a constant-temperature aging box and an XLPE sample section vibration mechanism arranged inside the constant-temperature aging box. The XLPE sample section vibration mechanism consists of a vibration table (1), a fixed rod (2), a fixed table surface (3) and a sample section fixed clamp (4); and an electromagnet and a frequency converter are arranged in the vibration table (1). In addition, the method includes: step one, sampling and processing are carried out on an XLPE insulated sample section and the processed sample section is fixed at the fixed table surface (3); step two, the vibration table (1) is electrified, a test temperature of the thermal-vibration combined aging testing apparatus of the XLPE insulated sample section is set, and a vibration frequency and amplitude of the vibration table (1) as well as test time are set; and step three, testing is started and the XLPE insulated sample section is taken out after testing completion to carry out analysis and testing.