The relative bioavailability of roxithromycin dispersive tablet in healthy volunteers was evaluated in this study. Its concentration in plasma was detected by high performance liquid chromatography (HPLC) after twenty healthy male volunteers were given each a single dose of 300 mg roxithromycin. The experiment data were obtained using DAS programme. The values of Cmax were 10.16+/-1.46 and 10.34+/-1.66 microg x ml(-1) at 2.33+/-0.61 and 2.28+/-0.62 h respectively; of t1/2 were 9.00+/-1.58 and 8.68+/-1.66 h respectively; of AUC0-->Tn were 143.32 +/-25. 80 and 138.93+/-22. 49 microg x h x ml(-1) respectively; of AUC0-->infinity were 158.63+/-26.86 and 153.77+/-24.75 microg x h x ml(-1) for test and reference drugs. Relative bioavailability of the tested roxithromycin was 103.63%+/-14.04%. The result showed that the two dispersive tablets are bioequivalent.