Recently the development of micro/nano satellite induces another study upsurge around the world. This paper attempts to discuss the application of the micro/nano satellite in satellite navigation. Firstly, the development status quo of the micro/nano satellite is reviewed, and the characteristics of the micro/nano satellite are analyzed. Then the three application modes of the micro/nano satellite in satellite navigation are given, which are respectively regional augmentation, navigation warfare and ionosphere observation and experimentation.