Objective:To analyse the drug resistance of Stenotrophomonas maltophilia(Sm) for rational application of antibiotics in clinics. Methods:Antimicrobial susceptibility tests were processed by K-B method, metallo-?-lactamases (MBLs) were screened by synergic method, and extended-spectrum ?-lactamases (ESBL) were detected by double disk synergy test. Results:42 Sm strains were completely resistant to imipenem, highly resistant to cefotaxime (CTX), amikacin (AMK), aztreonam (ATM) and piperacillin-tazobactam (TZP) (the resistance rates were 92%,83%,78% and 64%, respectively). They showed low resistance rates to sulfamethoxazole/trimethoprim(SMZ/TMP), cefoperazone/sulbactam(CFS), ciprofloxacin (CIP) and ticarcillin/clavulanate (TIM)(26%,16%,12% and 9%, respectively). There were 71.43% strains of Sm producing ESBL, 80.95% producing MBL, and 57.14% producing both ESBL and MBL. Conclusion:There are many kinds of mechanism contributing to the drug resistance of Sm, to which more attention should be paid by clinicians.