OBJECTIVE To study the relative bioavailability of glipizide sustained-release capsule in healthy volunteers.METHODS The plasma concentrations of gliplzide sustained-release capsule and controlled-realease tablet were determined with HPLC in 16 healthy male volunteers after 10 mg orally single dosage and multiple dosage.The pharmacokinetic parameters and relative bioavailability of two drugs were calculated.The c_maxand AUC_0～36were used to evaluate the bioequivalence of the two drugs with analysis of variance and double single t-test.RESULTS The concentration-time curves of these two drugs had two peaks.The stable phase could be attained after the drugs were taken in consecutive 4 days.The main pharmacokinetic parameters between single dosage and multiple dosage had no singificant difference by statistic analysis.CONCLUSION The glipizide sustained-release capsule was bioequivalent to the glipizide controlled-release tablet.