Glipizide sustained-release tablets were prepared with high-viscosity HPMC and Carbopol as sustained release materials by wet granulation. The accumulated release of glipizide at 4, 8, 12, 16 and 24 h in 0.015 mol/L hydrochloric acid containing 0.25% sodium dodecyl sulfate were (29.9 ± 3.2)%, (55.0 ± 2.0)%, (78.9 ± 2.1)%, (89.6 ± 1.9)%, and (99.3 ± 1.5)%, resp. The correlation coefficient of in vitro release and in vivo absorption was 0.9833. The results showed that in vitro and in vivo correlation of the sustained-release tablets was good (P < 0.001).