Shrimp farming is an important source of revenue and employment in many developing countries . However,infectious diseases have adversely affected the profitability of shrimp industry. For this reason,disease prevention is a priority and shrimp immunology has become a crucial research area of this field. In this paper ,the current importance and problems of shrimp2culture were described and the research advances in shrimp immunological defence mechanisms were summarized. The immunological tools are powerful and useful to evaluate the health state of the shrimp. The immunologies of shrimp mainly consist of cellular immunity and humoral immunity. In regard to cellular parameters , they are composed of haemocyte count (THC) , differential haemocytecount (DHC) and reactive oxygen intermediates (ROIs ). The immunity cells exert their defence functions through phagocytizing , enveloping , etc ,and the changes of THC and DHC are related to health state of shrimp. The ROIs generated during post phagocytic event which maybe an important marker to evaluate the immunological capability and phenoloxidase activity have been considered as a potential marker which is relevant to the health of the shrimp too. Concerning humoral parameters , prophenoloxidase (ProPO) and phenoloxidase , antimicrobial peptides and proteins , hemagglutinin and plasma proteins were described. The determining methods of immunity parameters were discussed. The response of shrimp to pathogens such as bacteria , virus , etc. and environmental factors such as DO , pH, etc , were also reviewed. It is well2known that the immune responses induced by immunizing crustacean or shrimp are mainly the non2specific immune responses. The potential of immunological parameters , including the changes of THC and DHC , the production of ROIs , phenoloxidase (PO) activity , antibacterial activity of plasma , and so on , to appraise the healthy state of shrimp were partly discussed. The future directions for the evaluation of the immunological capability of shrimp were proposed.