In this study, we can measure the permeability of Marshall specimens by modified osmotic pressure meter, which is improved by osmotic pressure meter. We get different voidage Marshall specimens and rutting plates by changing compaction times and rolling times. Modified osmotic pressure meter measures the permeability of Marshall specimens. Pavement ooze water meter measures the permeability of rutting plates. The results showed that: Because of the internal air, side sealing and different formula, the permeability coefficient measured by Pavement ooze water meter is not accurate. Modified osmotic pressure meter eliminates many adverse effects when we measure the permeability of asphalt mixture. So the correlation of voidage and permeability coefficient is better.