In this work, numerical simulations of straight-type and ladder-type cascade electrostatic fields consisting of three independent electrode plates were performed. The influence of the main structural parameters on the field intensity distribution and motion behavior of the charged particles in the electrostatic field were considered. The separation characteristics of charged particles in the two types of cascade electrostatic fields were comparatively analyzed. The simulation results were evaluated using high-speed dynamic image analysis and charge-to-mass ratio tests. The results show that the cascade distribution of electrostatic field intensity was more pronounced in the ladder-type structure than in the straight-type structure. The separation performance of different charged particles was better under the conditions of electrode plate spacing of 347 mm, electrode plate angle of 15°, and voltage gradient of 20 kV. The simulation results agreed well with the experimental results. This study provides new insights for realizing cascade triboelectric separation of minerals.