This paper presents the results of an investigation into the physicochemical properties of bivalve shells in Vietnam’s marine environment. It also proposes a technology for processing these shells into calcium carbonate powder to be used as a raw material for interior wall paint. The research results indicate that, although both oyster shells and clam shells primarily consist of calcium carbonate minerals, oyster shells contain carbonate minerals in the form of calcite, while clam shells contain carbonate minerals in the form of aragonite. This study used a temperature of 700 ℃ to completely burn off the organic binders and impurities in oyster and clam shells, obtaining pure calcium carbonate, which was then used as a raw material in interior wall paint. The paint demonstrate better adhesion, abrasion resistance, and durability in tropical climates compared to paint made with natural calcium carbonate powder.