Abstract: In this paper, the COMSOL Multiphysics simulation software is used to establish a three-dimensional model of a UV sensor patch with an interdigital electrode structure, and its electrical characteristics are studied. In order to reduce the initial resistance of the sensor and facilitate the measurement of the back-end circuit, a number of different simulation models are set up based on the structural parameters such as the width, spacing, and thickness of the interdigitated fingers by using the control variable method. Under the current physics interface in the AC/DC module, a steady state study is selected, and the results show that different structural parameters will have an impact on the electric field distribution and initial resistance of the electrodes and sensors. Through observation and analysis, it is found that the finger width of the interdigital electrode is 0.6 mm, the spacing is 0.4 mm, and the initial resistance is the smallest when the thickness is 5 μm. In addition, a new annular interdigitated electrode structure was designed, and its related electrical properties were initially explored. It is found that its initial resistance value is in the same order of magnitude as the optimized rectangular interdigital electrode, which has a good guiding significance for relevant practical experiments.