The investigation took place within the Northern Bay of Bengal, where vital seawater data was gathered across 36 stations. Utilizing Conductivity, Temperature, Depth (CTD) instruments, essential parameters including temperature, salinity, density, photosynthetic active radiation, pH, turbidity, nitrogen concentration, dissolved oxygen, fluorescence, and sound velocity were meticulously recorded. This data collection effort was conducted during a collaborative oceanographic expedition involving the Department of Oceanography and the International Centre for Ocean Governance at the University of Dhaka, with support from the Bangladesh Navy. The resulting dataset is available in both CSV and NetCDF formats and serves as a cornerstone for comprehending the physicochemical characteristics of the region.