A metal film with higher work function is deposited at the output electrode of the microchannel plate to cover the original nickel-chromium electrode, which further reduces the kinetic energy of the output electrons of the microchannel plate and the dispersion of output electrons on the phosphor screen, thus improving the resolution of the microchannel plate. The experiment results show that the resolution of the image intensifier increases by 6.6% from 60 lp/mm to 64 lp/mm when a 20 nm thick silver layer with work function of 4.3 eV is deposited on the output electrode of the microchannel plate, while the resolution of the image intensifier increases by 13% from 60 lp/mm to 68 lp/mm when a 20 nm thick platinum layer with work function of 6.4 eV is deposited on the output electrode of the microchannel plate. At the same time, the gain of microchannel plate decreases. For silver plated microchannel plate and platinum plated microchannel plate, the gain decreases to 74% and 33% of the original value respectively. The higher the work function of metal film, the higher the percentage of resolution improvement, and the higher the percentage of gain decreases. Therefore, when the proposed method is used to improve the resolution of microchannel plate, it is necessary to use the microchannel plate with higher gain, so as to make up the influence caused by the decrease of microchannel plate gain.