The chapter is devoted to study of the authigenic mineralization in the sediments on the Vietnamese shelf. The study revealed that forming of authigenic sulfides and carbonates in the Quaternary sediments of the southwestern part of the South China Sea had been associated with various processes. The isotopic composition of carbonates can be formed by oxidized methane or diagenetic carbon dioxide. Sulfides in this area were formed in the result of both diagenetic and hydrothermal processes. The localization of sulfide mineralization in near-surface sediments in specific points can be explained by the small thickness of unconsolidated deposits, their fine-grained structure, and favorable endogenous conditions.