This paper mainly reviewed the progress on immunological mechanism in Mollusks. Haemocyte phagocytosis represents the main aspects of the entire cellular immunity in mollusk. The humoral factors constituted by lgsosomal enzymes, agglutinius, antimicrobial peptides participate in mollusks＇s immunity. through the killing of bacteria, promoting phagocytosis and other ways. The molecules such as opioid peptides,cytokines,protein kinase（PK） and so on are chemical mediators which mediate immunce signal trausfer in immune defeuse. The research on s...
