Pharmacokinetic (PK) parameters of marbofloxacin (MRFX) in Korean cattle, Hanwoo, were determined following its intravenous (i.v.) or intramuscular (i.m.) administration at a dose of 2 mg/kg. Area under the curve (AUC0-24 hr), half-life (t1/2) and total body clearance (CLB) of i.v. MRFX were 6.87 hr∙µg/ml, 2.44 hr and 0.29 l/kg∙hr, respectively, and the corresponding values for i.m. administration of MRFX were 5.07 hr∙µg/ml, 2.44 hr and 0.39 l/kg∙hr. The suggested optimal doses of MRFX in Hanwoo cattle, calculated by integration of PK data obtained in the present study and previously reported minimum inhibitory concentration (MIC) for MRFX against susceptible (MIC ≤1 µg/ml) and intermediate (MIC ≤2 µg/ml) pathogenic bacteria, were 2.1 and 4.2 mg/kg/day by i.v. route and 3.9 and 7.8 mg/kg/day by i.m. route.