The difficulties in the simulation analysis of capacitance imaging sensor are discussed in this paper, using the eight electrode capacitance imaging sensor as an example, three dimensional finite element simulation mathematical model of capacitance sensor is established, this paper introduces how to use COMSOL software for three dimensional simulation of capacitance imaging sensor,postprocessing results show that the eight electrode capacitance imaging sensor can detect the defects in the inner surface of the glass with seven different depths, the feasibility of capacitance imaging detection technology is verified. In addition, COMSOL is used to extract and analyze the capacitance value of the eight electrode capacitance imaging sensor, and the results are compared with the experimental results. This method is convenient for the research on the problem of capacitance imaging detection technology, and provides the basis for the performance analysis and parameter optimization of the capacitance sensor using COMSOL software.