The absorption, distribution and elimination of flumequine in orange-spottedgrouper Epinephelus coioides were studied after various routes of administrationat 23oC. The area under the serum concentration-time curve (AUC) was 249 gh/ml after the fish was given a single intravenous injection at a dose of 20mg/kg b.w. Distribution and elimination half-life (t1/2, t1/2) of flumequinewas 0.3 and 10.5 h, respectively. The drug was absorbed and eliminated rapidly.Flumequine reached a peak concentration (Cmax) of 42.3 g/ml in serum. Asteady-state level of flumequine was achieved on the 2nd day in serum, muscle,liver and kidney of fish after four consecutive days of oral administration atdose of 20 mg/kg b.w./day, and an average concentration (Css) of flumequine inserum was 4.6 g/ml. The peak of flumequine concentration in serum was 1.2 g/ml on the 3rd day after consecutive bathing administration at dose of 20 ppmfor three days. The bioavailability of oral and bathing administration was 44and 9%, respectively.