Surface flashover degrades insulation performance in high-voltage systems, making its control a critical requirement. Therefore, we have developed a device capable of conducting flashover experiments in vacuum as part of efforts to enhance insulator performance. This experimental setup is designed to perform time-resolved imaging of flashover process using an ICCD camera. The developed device features a rotatable electrode-insulator assembly, enabling the transition from conventional 2D imaging to 3D imaging. Temporal imaging will capture key moments, including the initiation of voltage drop, the point of maximum voltage, and post-discharge phenomena. For voltage measurements, a Capacitance Voltage Divider (CVD) is attached to the chamber wall near the electrode, ensuring accurate measurement of the voltage. Current measurements will utilize a Rogowski groove capable of covering tens of MHz of bandwidth, ensuring future expandability. Based on the results obtained in this study, we anticipate elucidating the multipactor process in terms of voltage and current perspectives coupled with imaging. These are expected to contribute to the development of multipactor suppression methods for controlling flashover in high-voltage applications.