In 2022, BGP carried out a high-density 3D seismic acquisition project in the Caspian Sea. The water depth ranges from 6.5m to 40m in the survey area. It is a complex offshore oil field with many operational challenges to face, numerous densely distributed platforms and subsea oil pipelines, the various water depth caused submarine volcano and difficult final processing imaging. This paper tends to present results of the integrated OBN acquisition and processing for this challenging survey. For field acquisition, a suitable geometry was designed to meet geological objectives, and field operational scheme was optimized considering in the congested oil field with flexibility of ocean nodes; The quality control technology of massive node data was applied, which provided a powerful guarantee for data quality. For data processing, integrated seismic processing strategy was performed to ensure final imaging for this complex shallow data and initial results have encouraged structural seismic images profitable to interpretation.