Abstract: Through the observation of cores and well logging data using sedimentological methods, the types and characteristics of sedimentary microfacies of the Xijiang 24-3 Oil Field have been carefully studied.It reveals that deltaic plain and deltaic front deposits dominate the sequence. 8 types of microfacies are recognized. We grouped the microfacies in accordance with their temporal and spatial distribution. It suggested that the reservoirs of the region mainly consist of the microfacies of distributary channels in the delta plain, and the subaqueous distributary channels, mouth bars, distributary bars and sand sheets in the delta front.They are the favorable targets for further exploration.