Abstract: The anti-ion feedback film of the microchannel plate in a third-generation micro-optical image intensifier protects the photocathode from bombardment by feedback ions and prolongs the device lifetime; however, it also affects the quality of the electronic image. Based on the Monte Carlo analysis method, the electron transmission characteristics of the anti-ion feedback film in the microchannel plate of a third-generation micro-optical image intensifier were studied. In addition, the electron transmission characteristics of the anti-ion feedback film were measured and compared using a half-film experiment. The results showed that for an anti-ion feedback film with a thickness of 5 nm, the electron transmittance was approximately 60% when the proximity voltage in front of the image intensifier was 400 V, and the electron transmittance was approximately 80% when the current proximity voltage was 600 V. The electron transmittances of the anti-ion feedback films were 56.6% and 85.0%, respectively, and the maximum relative deviation between the experimental and analytical results was less than 6.3%, indicating that the electron transmittance of the anti-ion feedback film of the third-generation micro-optical image intensifier microchannel plate could be obtained using the half-film method. The results of this study are significant for improving the fabrication quality of anti-ion feedback films in third-generation micro-optical image-intensifier microchannel plates.