AbstractClick here and insert your abstract text. Physical properties of reservoir and seal-layer samples are essential information to evaluate the storage and seal potential and to predict long term CO2 behaviour in reservoir. In this study, we measure the elastic wave velocities (Vp and Vs), porosity and density of sandstone, limestone and lime-mudstone samples are measured of Ngrayong Fm. and Bulu Fm, Central Java, Indonesia. The sandstones indicate low Vp, Vs, density and high porosity. These results suggest that sandstones on Ngrayong Fm. have large porosity and became important candidate of CO2 reservoir. On the other hand, lime- mudstone indicates high velocities with low porosity and point out that they have enough potential to be sealing layer of injected CO2.