Abstract: The reservoir of Sand Set-3 of Member-1 of Zhujiang Formation is very poor in physical property in Wenchang A Oilfield, with low longitudinal tracing accuracy in seismic section. Fine description has been conducted on plain distribution of sand bodies by abstracting and clustering seismic attributes, and optimizing seismic attributes which are highly related with reservoir parameters. According to the analyzing results, it is concluded that the seismic attributes, such as RMS-amplitude and min-amplitude, are highly related with reservoir parameters such as reservoir thickness and porosity. The sedimentary microfacies can be described finely by using the relationship among the parameters. This technology is very significance in guiding the development and adjustment of low permeability reservoirs and digging the development potential of this kind of reservoirs.