This study was attempted to investigate the pharmacokinetic interaction of vancomycin (10 mg/kg, i.v.) and probenecid (7.5. 15, and 30 mg/kg, oral) in rabbits. The area under curve (AUC) of plasma vancomycin concentration was significantly increased (p<0.01) in rabbits when the probenecid was coadministrated. Volume of distribution (Vd) was significantly decreased (p<0.05) in rabbits coadministrated with probenecid (15 and 30 mg/kg) and total body clearance (CLt) was decreased significantly (p<0.05. p<0.01) in rabbits coadministrated with probenecid (7.5, 15 and 30 mg/kg). There was significant correlation between AUC and probenecid dose. From the results of this experiment, it is desirable to adjust dosage regimen of vancomycin for reduction of side or toxic effect when the probenecid is coadministered in clinical practice.