The invention discloses an insulation aging evaluation method for a 110kV XLPE high-voltage cable. The method comprises the following steps: testing polarization current and depolarization current ofthe high-voltage cable in a polarization process and a depolarization process through polarization-depolarization current (PDC); obtaining a low-frequency dielectric loss factor under the corresponding polarization voltage according to the obtained polarization current and depolarization current; and evaluating the insulation performance of the high-voltage cable by taking variation of the low-frequency dielectric loss factor under different polarization voltages as a characteristic quantity for representing the insulation aging of the cable. Thus, the insulation aging state of the high-voltage cable can be diagnosed efficiently, and reflected more accurately, the sensitivity is high, and the method can be widely applied in the field of cable insulation aging diagnosis in future.