Bioactive principles present in the medicinal plants attribute to the therapeutic efficacy and it can be incorporated into modern medicine system for the development of newer drug formulation for therapeutic ailments. Screening of medicinal plants for antimicrobial activities and phytochemicals is important for finding potential new compounds for therapeutic use. In the present study an attempt has been made to congregate the traditional, phytochemical and pharmacological studies done on an important medicinal plant Annona muricata. The plant possess the major pharmacological activities includes Anti-viral activity, Anti-oxidant Activity, Larvicidal activity, Antiinflammatory activity, Antipediculicidal activity, Anti-bacterial activity and wound healing. It also has the anti-carcinogenic and cytotoxic effect. The present study revealed that immunostimulant A. muricata extract fed Fenerropenaeus indicus exhibited had increased total haemocyte count, oxyhaemocyte count and decreased time of coagulase activity. The biochemical parameters such as protein and carbohydrate and immunological parameters were significantly (P < 0.01) differed from the control groups to experimental groups.