The Upper Guantao Formation in west 7th Block of the Gudong Oilfield，Jiyang Depression，is dominated by meandering fluvial deposits， among which two large point bar sandbodies were developed in the layer Ng522. Based on the systematic characterization of subsurface reservoir architecture of point bar reservoir， the geometry modeling method of architectural bounding surface is investigated here， and the architectural bounding surface model is embedded into the facies model based on the 3D structured grid mesh. The 3D reservoir architectural modeling of well 26-295 area is established， and it is more accordant to the practical formational conditions in a real meaning. The spatial distribution characteristics of architecture element and bounding surface within the microfacies are reconstitued excellently， which meets the requirements of 3D numerical reservoir simulation. The results show that lateral accretion beds in the point bar are inclined to the abandoned channel and extend to the position of  2/3  to the top of point bar which is presented as “semicommunicated sandbody”. The remaining oil distribution patterns within point bar sandbodies are established and the potential exploitation measures are proposed. The application effects of the reservoir architecture characterization and modeling in the study area are good and can be applied to other similar oilfields. It has important significance both in enriching reservoir geology theory and enhancing exploitation efficiency of reservoirs.