Abstract：Modeled ( 1:10) sedimentary series with a borehole and micro acoustic loggrog tool are taken to form a laboratorial system for analysing the propagation mechanism of acoustic wave in borehole. High frequency acoustic source is used to bring all-wave train which shows quite clear compressional and shear waves，and low frequency acoustic source is introduced to generate quite good Stoneley wave.With increase of porosity and permeability，bath shear wave and pseudo Rayleigh wave attenuate greatly;and Stoneley wave also attenuates hard and hard(Especially its high frequency content attenuates more severe than the low frequency content),its velocity reduces obviously，and its dominant frequency removes toward low frequency side. Reflected Stonely wave occurs when there are horizontal fractures which intersect borehole，and its reflection coefficient is directly proportional to fracture width and I}as something to do with permeability and filling materials in fracture interval.
