The pharmacokinetic disposition of Cepharanthin, a biscoclaurine alkaloid, was investigated in healthy subjects following single intravenous doses of 25, 50, and 100mg and during and after the 7 days repeated doses of 100mg per day . Each dose was studied in 5 subjects. Plasma and urine Cepharanthin levels were measured by the HPLC method and were analyzed by the one-compartment open model. Linear relationships were obtained between the dose of 3 doses of Cepharanthin and the Cmax or the AUC . The t1/2 ranged from 31.8 to 36.9 hr. The steady state levels were obtained for 5 to 6 repeated doses of 100 mg/day approximately and following the 7 repeated doses the mean (±SE) of t1/2 was 62.0±2.8hr. Using our previous study results of oral dosing, we obtained 0.06 to 0.09 of the absolute bioavailability of Cepharanthin. Total recovery amount of unchanged drug was 9. 6% of administered dose. Throughout the studies we did not observed any adverse effects. These results suggested that Cepharanthin could be extensively metabolized in liver and largely uptaken to the tissue, binding strongly.