Abstract: Serratia marcescens is the most common Serratia species in clinical infection. As an opportunistic pathogen, it can cause opportunistic hospital-associated infection. S. marcescens exhibits intrinsic drug resistance to multiple antibacterial agents, and clinical isolates often demonstrate multidrug resistance, and making infections challenging to treat. This paper reviews the progress of research on the drug resistance of clinical S. marcescens isolates, including resistance profiles, resistance rates and potential resistance mechanisms, aiming to provide references for clinical treatment and further studies on its resistance mechanisms.