Abstract: The Fuyu oil layer, located in the southern Daqing Placanticline within northern Songliao Basin, contains well-developed sandstone reservoirs, holding significant potential for increasing the reserves and productivity of the Daqing Oilfield. These reservoirs are characterized by porosity ranging from 9.0% to 13.6% and permeability between 0.1 mD and 3.21 mD, representing tight sandstone reservoirs. Their development requires horizontal wells and large-scale volume fracturing, thus placing high requirements on the accuracy of sand body prediction. These reservoirs are primarily concentrated in the Fuyu I and II oil formations, deposited predominantly in a deltaic plain subfacies. In these formations, the sand bodies are characterized by frequent lateral variations, small single-layer thickness, and a staggering and overlapping vertical distribution pattern. These characteristics result in complex seismic responses, posing great challenges to reservoir prediction. In view of the sedimentary characteristics of tight sandstone reservoirs in the Fuyu oil layer, this study employed development-scale seismic sedimentology for sand body prediction. Specifically, through seismic forward modeling based on well parameters, the seismic responses of thin tight sandstones were identified, followed by the integrated application of automated optimization of stratal slices and planar quantitative prediction of sandstone thickness. The results reveal a positive correlation between seismic amplitude and the thickness of sub-layer sandstones in the Fuyu oil layer, southern Daqing Placanticline. The development-scale seismic sedimentology technology quantitatively characterizes the planar distribution of sub-layer sand bodies, strongly supporting the successful well placement and implementation in the horizontal well pilot area. The success in the trial development of tight oil via horizontal wells in the Fuyu oil layer, Block M2, southern Daqing Placanticline, sets an example for tight oil development in the northern Songliao Basin. Therefore, the development-scale seismic sedimentology for sandstone prediction shall be given a high priority in the subsequent horizontal well design and implementation. This ensures a high penetration rate of sandstones and oil layers and provides technical support for developing tight oil resources in the Fuyu oil layer.