The majority of the discovered oil reservoirs of Yan 9 Oil Group in the Ordos Basin are located in the distributary channel sandbodies of meandering river delta plains. The superposition relationship of single sand body within these sandbodies is complicated and varied, and the influence law of oil development is not clear. Taking the Yan 9 Oil Group in the G162 Area of the Jiyuan Oilfield as an example, the vertical and lateral overlapping relationships of single sand bodies and the connectivity of sand bodies were deeply studied based on core, logging data, testing oil and gas production, production dynamics, and analytical tests. The effect of the superimposition relationships of single sand body on waterflood development was revealed. The results indicate that the vertical superposition relationship of single sand body in the target layer in the study area is mainly in the form of cut-and-stacked, accounting for 64%. The lateral superposition relationship of single sand body is mainly the same channel type and the side-cut type, accounting for 57%. Among these, single sand bodies in contact with cut-and-stacked type and same channel type exhibit good connectivity, while the rest show weak or poor connectivity. Within the distributary channel microfacies parallel to the provenance direction, single sand bodies are mainly in the form of cut-and-stacked type and same channel type, leading to good injection-production correspondence and effective waterflooding effect. In contrast, within the distributary channel microfacies perpendicular to the provenance direction, single sand bodies mainly exhibit superimposed type and side-cut type, resulting in weaker injection-production correspondence and average waterflooding effect. In the wing microfacies of the distributary channel perpendicular to the provenance direction, single sand bodies are primarily isolated, side-cut, and bay-contact types, which correspond poorly to injection-production correspondence, and relatively poor waterflooding effect. So, the effectiveness of waterflood in different well groups in the study area is influenced by factors such as sedimentary microfacies, provenance direction, and superimposition relationships of single sand body.