Over the past decade, there has been a surge in marine sand exploration and the public transfer of marine sand mining rights. Approximately 390 million cubic meters of marine sand resources have been transferred in the coastal regions of Guangdong, Guangxi, and Fujian. However, the classification of marine sand sediments remains challenging due to the variety of methods in use and the lack of a mature, unified classification system. Addressing this urgent technical issue, a suitable classification method for marine sand sediments has been proposed based on exploration practices in the waters surrounding Hainan Island. By comparing different classification methods and their application effects, this proposed scheme is represented by a diamond diagram, categorizing nine sediment types: gravel (G), sandy gravel (sG), muddy gravel (mG), gravel sand (gS), gravel mud (gM), sand (S), muddy sand (mS), sandy mud (sM), and mud (M). Additionally, a subdivision scheme has been introduced to align closely with the Folk classification method. This classification scheme is both descriptive and explanatory, concise, and emphasizes the significance of each grain grade's content, including gravel, sand, silt, and clay. It ensures practicality for sediment classification of field operations and paves the way for further laboratory research.