Abstract: The extracts of marine mollusks（Abalone，Aplysia，Sepia，Arcagranosa linnaeus，Cyclina sinensis，Mytilus coruscus，Chlamys farrei，Meretrix meretrix，Ostrea，Sinonovacula constricta and Solen gradis）classified as polysaccharides，proteins and peptides，possess the antitumor，anti-aging，and anti-bacterial activities.Cancer patients undergoing long-term chemotherapy usually suffer from the damage to vital organs，and resistances affecting the outcomes of chemotherapy.Therefore，it is imperative to search for anti-cancer drugs with low toxicity and high efficiency.At present，several marine mollusks are being studied.Summary on the antitumor activities of the marine mollusks extrats is presented，which might provide a basis for the development of marine anti-cancer drugs.