Abstract: The high acquisition cost of OBN (ocean bottom node) seismic technology has affected its widespread application to some extent. Therefore, conducting research on the degradation of OBN geometry is of great significance for improving acquisition efficiency and reducing acquisition costs. Based on the OBN seismic data acquired in South China Sea, this study analyzes the degradation of OBN acquisition parameters such as number of acquisition lines, node spacing, and maximum offset. It clarifies how these parameters impact seismic imaging and buried hill fracture prediction, laying a foundation for exploring more economical and efficient OBN acquisition geometry. The findings can provide guidance and reference for optimizing OBN acquisition designs to meet diverse offshore exploration needs.