Dielectric tests such as high voltage withstandtest is important to verify whether the electrical devices are in reliable working condition or not. This paper presents a novel high voltage dielectric test system up to 160kV AC based on resonant circuits using the magnetically controllable inductance. Firstly, the working principle and the design of the magnetically controllable inductance are introduced. In addition, a finite-element model is completed and analyzed to verify the designs of the magnetically controllable inductance. Next, resonant circuits and the control scheme of the dielectric test system are described. Finally, the proposed testing system is simulated using PSCAD/EMTDC. The test system can perform series or parallel resonance AC tests by adjusting the inductance in the resonant circuit to meet the various requirements of the equipment to be examined. Compared with the conventional high-voltage test systems, the proposed test system has the advantages of compact structure, stable output voltage, and strong adaptability of the test method.