With continuous development and improvement of the microchannel plate production technology, it becomes more and more difficult to enhance its performance by improving traditional crafts. New technologies and new crafts of microchannel plate need to be developed urgently. Development of nano film material and mature preparation technology provide an excellent opportunity for the development of microchannel plate. The channel inner walls are deposited with layer of alumina nano film as secondary electron emission layer by using atomic layer deposition technology, it can increase the secondary electron emission coefficient of channel walls as well as the gain of microchannel plate. The alumina nano films can be deposited in the channel inner walls uniformly with optimized process parameters. The results show that microchannel plate gain changes with alumina thickness, especially it will achieve a high gain up to 56 000 which is about 12 times the gain of normal microchannel plate when the bias voltage is 800 V and the alumina thickness is 60 cycles.