The fan deltas developed widely in several faulted basins in China. As a kind of important oil and gas reservoir，it is very necessary to make the internal architecture clear for prediction of the residual oil distribution in the late period of oilfield development. Therefore，taking the 5th Zao oil layer of Kongdian Formation in the faulted block Guan195 of Wangguantun Oilfield as an example，the reservoir architecture of fan delta front was characterized quantitatively based on core data，well logs and production data. The main reservoir architecture elements of fan delta front consists of distributary channel，estuary sandbar，sheet sand and inter channel. And then the division scheme was established for the division of reservoir architecture of fan delta front into different levels，and the markers was defined for the identification of distributary channel estuary sandbar and inner accretion body in estuary sandbar. Taking single sandbody as a unit，data，being acquired from field outcrop defined as fan delta in the Xiguayuan Formation of Luanping Basin，were matched to derive a formula for quantitative characterization of distributary channel and estuary sandbar，calculation of the dip of interbed inner estuary sandbar and prediction of the development of inner accretion body. The residual oil controlled by a single genetic sand body distributes at the top of the margin of sandbars and channels，and the distribution of residual oil controlled by the interlayer should be analyzed according to the specific rhythm of the sandbar.