Electron bombarded Active Pixel Sensor (EBAPS) is well known for its low noise in low-light level imaging, high mechanical integration, and a relatively low cost. It plays an important role in areas of the industrial process as well as the fundamental scientific research. However, the performance of EBAPS is intensively influenced by the structural parameters (i.e. the acceleration voltage between cathode and anode, thickness of the passivation layer, etc.). Due to the influence of these factors mentioned above, the performance of EBAPS is restricted to achieve its best condition. Herein, a model based on the optimized Monte Carlo method was proposed for effectively analyzing the scattering behavior of electrons within the electron multiplier layer. Unlike traditional simulation, which only deals with the electron scattering in longitudinal, in this paper, we simulate the electron scattering character not only in horizontal but also vertical among the multiplier layer, which would react to the influence induced by structural parameters more complete and more precise. Based on the proposed model, an experimental prototype of EBAPS is built and its detection sensitivity achieves 0.84 x 10(-4) lux under spectral response of ultraviolet (UV) spectroscopy, which improved a lot from our former design. The proposed model can be used for analyzing the influence induced by structural parameters, which exhibit enormous potential for exploring the high-gain EBAPS.