Abstract：The longitudinal wave velocity was used to review the mechanical properties of marble specimens which were compressed under confining pressure and coarse sandstone specimens which were heated to various temperatures. Rock is not a kind of linear elastic material. The longitudinal wave velocity，Young¢s modulus and strength are different macroscopical behaviors of rock mechanical properties. There is a clear inverse correlation between strength and longitudinal wave velocity of specimens. It can be explained as that marble has been compressed by geostresses and the lower strength in a local place would result in the lower stress on the material neighborhood and better contact among crystals. Marble specimen was damaged continuously during compression under confining pressure while the bearing capacity keeps constant. The damage in specimen changes with confining pressure and axial deformation. The longitudinal wave velocity，uniaxial strength and Young¢s modulus of damage specimens only have a positive statistic correlation roughly，but there are some exceptions. Sandstone is made of mineral particles and cement. The cement will be weakened after heated，which results in the decrease of longitudinal wave velocity and initial modulus. But thermal deformation may improve the contact state of mineral particles departed by fissure，so the average modulus is nearly the same and strength becomes higher before temperature increases to 500 ℃，after that the average modulus and strength decrease with temperature.
