In recent years，much attention has been focused on the braided fluvial delta reservoir in which reservoir architecture directly controls hydrocarbon enrichment and distribution. Take the lower oil layer in the1st block of Tahe Oilfield as an example，a set of systemic methods to analyze the architecture of the braided fluvial delta reservoir were proposed by combining modern sedimentation measurement with empirical formula for forecasting. Based on the sedimentary facies analysis，according to comprehensive analysis of core data，well logs，seismic and mudlog，different hierarchical levels of architectural interfaces and the corresponding architectural elements were identified. After the identification of barrier-intercalations，using the analytic hierarchy process，the reservoir in the study area was explored into three hierarchial levels including single channel，channel bars and single accretion of channel bars，which were then characterized quantitatively. The results show that the single braided channels are 128-690 m wide，underwater distributary channels are 144-386 m wide，single channel bars are approximately 244 m wide and 594 m long of the lower oil layer in the study area. The channel bars are characteristics of well-developedinterlayerswith inclined angle of 2°-4° on the meeting water side and less than 1° on the back water side in the long axis.