Abstract: The emergence of multi-drug resistant bacteria has brought great challenges to clinical anti-infection treatment, and tigecycline, a new tetracycline drug, is used as the“last line drug”. But in recent years, there have been many reports of tigecycline resistance.This paper summarizes the mechanisms of tigecycline resistance, including active efflux pump, gene mutation and Tet family, to provide more ideas for the prevention of multi-drug resistance to tigecycline