The invention discloses a method and a system for evaluating the ageing life of a crosslinked polyethylene insulating cable for smart energy. The method comprises the following steps: accelerating a thermal ageing life estimation test, and introducing an electrical ageing factor in the thermal ageing life estimation test. According to the method and the system, electricity is introduced on the basis of a single factor thermal ageing estimation test, that is, the thermal ageing test is accelerated on a cable test specimen, and meanwhile a rated working voltage is applied to an insulating layer of the cable test specimen, so that the simulated ageing test conditions are in better accordance with an ageing process in a practical operating process of cable insulation; therefore, the evaluated life value which is more close to the actual life of the cable can be obtained; the method and the system have more guidance meaning on the transformation and replacement of a cable project engineering.