Objective: To compare the antibacterial effect of 12 antimicrobial agents on enterococci of clinical isolates during 1997~1998 in vitro. Methods: Minimum inhibitory concentration and minimum bactericidalconcentration of 12 antimicrobial agents to enterococci were examined with double dilution test. Results: 244 enterococci isolated in our hospital during 1997~1998 were collected in the study. Results showed that vancomycin and teicoplanin had the most potent antibacterial activity

with susceptible rates of 89.60% and 96.73%、respectively. Piperacillinampicillin and penicillin G also had better antibacterial activity. The resistant rates of enterococci faecium to 12 antimicrobial agents were higher than those of enterococci faecalis. MBC values of 12 antimicrobial agents to enterococci were as same as their MIC values or 1~2 times higher. MBC50 and MBC90 of 12antimicrobial agents to enterococci faecium were obviously higher than those of enterococci faecalis. Conclusion: Piperacillin

ampicillin and penicillin G had better antibacterial effect to enterococci. Vancomycin and teicoplanin were the best effective antibacterial agents in the examined antibiotics. Glycopeptide resistant enterococci were detected in the study and it is worth noticing.