In this paper, the reason of input signal loss caused by input electrode of Microchannel Plate (MCP) is analyzed, and a method of plating insulation layer on input end of MCP is proposed to increase the utilization of input signal of MCP which is verified by experiment. The experimental results show that a layer of 15 nm thick insulating layer is plated on the input end of the MCP, which can increase the utilization of the input signal of the MCP and the gain of the MCP. The higher the secondary electron emission coefficient of the insulating layer is, the higher the utilization ratio of the input signal of the MCP is, and the larger the ratio of the gain increase is. For SiO₂ films, the gain can be increased by about 12%. For Al₂O₃ films, the gain can be increased by about 35%. At the same time, the resolution and MTF of image intensifier will decrease slightly. Similarly, the higher the secondary electron emission coefficient is, the larger the decrease ratio of resolution and MTF is. However, the decrease ratio of resolution and MTF of MCP is much lower than that of gain increase. The method proposed in this paper to increase the utilization rate of input signal of MCP has certain practicability and can be popularized.