Abstract. Underwater cultural heritage (UCH) in Italy is under-documented despite its significance. Creating a comprehensive UCH database is essential but faces challenges, such as complex documentation processes, data interoperability, and international standard adherence. This paper examines data models, standards, and the use of webGIS and databases for underwater cultural heritage documentation in Italy and globally. International documents like the 1996 ICOMOS Charter and the 2001 UNESCO Convention emphasize in-situ preservation. However, documentation efforts remain scattered, lacking a unified database. GIS technologies are vital for managing and analyzing UCH data but are underutilized for public access and tourism. Projects like Andar per Mare and Archim3des in the Puglia region aim to promote underwater cultural heritage using webGIS platforms. However, existing sources like CartaPulia face limitations, including a lack of standardization, specialized fields for underwater cultural heritage characteristics, and language barriers. The proposed solution involves creating a new data model based on standards, resulting in a bilingual geodatabase. This geodatabase will support scientific and tourism-focused webGIS applications, enhancing accessibility and promoting Italy's underwater cultural heritage. A unified database will prevent duplication, facilitate discoveries, and promote Italy's cultural heritage.