The invention discloses a frequency-domain dielectric spectrum experimental system for a vehicle cable terminal under different temperature conditions. The frequency-domain dielectric spectrum experimental system is composed of a high-temperature heating simulation system, a low-temperature environment simulation system, a temperature control system and a frequency-domain dielectric spectrum test system; and the high-temperature heating simulation system is arranged in a cavity of the low-temperature environment simulation system, and the temperature control system and the frequency-domain dielectric spectrum test system are arranged outside the cavity of the low-temperature environment simulation system. On the basis of the experimental system, a provided experimental method can be used to simulate temperature change in a relatively wide range of the vehicle cable terminal and further conduct frequency-domain dielectric spectrum experiments of the vehicle cable terminal under the different temperature conditions, the economical and applicable performances are higher, and the system and method have significance in detecting and evaluating the insulation aging state of the vehicle cable terminal.