Endophytes are widely distributed in roots, stems and seeds of tobacco plants. It has been well documented that tobacco plants infected by endophytes are generally more competitive compared with uninfected plants, as indicated by better growth, stronger resistance to diseases and pests, and lower content of nitrosamines. This paper reviewed recent research progresses in biodiversity of endophytes in tobacco plants and their important role in tobacco cultivation, and summarized the functioning mechanisms of endophytes. Finally, the weaknesses in current research were discussed, and research perspectives were also proposed.