This research aims to achieve online monitoring of the breakdown position on the contact surface of the vacuum interrupter. This is significant for inspecting its insulation performance and enhancing conditioning methods. Currently, the structural characteristics of the vacuum interpreter limit the use of optical observation methods. In addition, the inverse problem approach, which depends on the known magnetic field to determine the distribution of the field source, has significant deficiencies in terms of uniqueness and accuracy due to the lack of support from boundary conditions. This paper proposes a method to invert the magnetic field source by utilizing signals detected by array sensors, enabling the localization of vacuum interrupter breakdowns. The arrangement of magnetic field sensors forms a ring within the cross-section at the center of the vacuum interrupter, aligning with the magnetic field distribution characteristics outside the vacuum interrupter during breakdowns. Simulation results from COMSOL illustrate a correlation between the magnetic induction intensity distribution characteristics of the specific sensor array mentioned above and the breakdown position. As a result, this establishes the measurement and inversion model discussed herein. In the experimental session, a total of 32 magnetic field sensors were uniformly arranged in a ring shape. A synchronous digital acquisition system formed the experimental platform. The experimental results validate the feasibility of the principle outlined in this paper. Furthermore, the detection outcomes achieve a positioning accuracy of 11.25 degrees in the circumferential direction and 1mm in the radial direction in polar coordinates.