Abstract: In order to effectively predict lithological reservoir position, Based on analysis of the origin of the underwater distributary channel in study area, and the seismic reflection configuration of the underwater distributary channel has been recognized using the reflection features of seismic event from the high resolution 3D seismic data. Then many interlaminar or along?horizon attributes of the seismic reflection wave of the interested sand group are extracted, including instantaneous amplitude, instantaneous frequency, instantaneous phase, root mean?square (RMS) amplitude, mean absolute amplitude, mean reflection power, instantaneous frequency slope, slope at half?life energy,arc length, mean reflection strength and lateral coherent feature, etc. By the multi?attribute combined correlation and the log?seismic data integration, it is finally determined to predict the spatial distribution of underwater distributary channel sand bodies using RMS attribute sections. The research shows that three typical reflectance features of vertical accretion, lateral migration and sand lens superimpostion, have been recognized on the seismic profile. The underwater distributary channel sand bodies appear large scale finger?shaped extension from the NE to the SW. The studied results have been confirmed by the drilling responses, which opens a new field of oil and gas exploration in Biyang sag