Abstract:36 formulae of reflection and transmission coefficients on anisotropic interface are derived from elastic wave equation in anisotropic medium. The computation result of P-P wave reflection coefficients in fractured medium says that on an interface consisting of vertical fractures and azimuthal isotropic medium, P-P wave reflection coefficient(absolute value)comes up to maximum in direction paralleling fracture, but gets minimum in direction perpendicular to fracture. Dip angle of fracture influences the AVO characteristic of P-P wave, minor dip angle resulting in gentler AVO phenomenon. On the interface where there are non-horizontal fractures, reflection coefficient of P-P wave has more extrema to show complexity and to fail to directly indicate fracture strike. In a word, the azimuthal AVO characteristic of compressional wave is close related to the azimuth, dip angle and density of fractures.