The polarization/depolarization current method is based on the dielectric response theory and is one of the nondestructive testing methods for the integral insulation state of crosslinked polyethylene cables. In this paper, a polarization-depolarization current test device for crosslinked polyethylene cables is developed, which is mainly composed of a high voltage circuit board, a current measurement circuit board and a current to voltage conversion module. This paper firstly introduces the principle of the polarization/depolarization current method and analyzes the shortcomings of the commonly used test devices; Then this paper introduces the structure of the developed device and focuses on determining the key parameters. Finally, a laboratory three-branch resistance-capacitance circuit is built to simulate the three-branch Debye model of the power cable and verifies the effectiveness of the developed device.