In the present study, an attempt has been made to explore the Immunomodulatory activity of Health’ Boost (HB) – a poultry feed supplement in Cellular and Humoral immune response rat model. Two doses of the trial drug (600 & 800 mg/kg) were administered in rats. The assessment of Humoral immunity was carried out by HA titre and was found to be significantly increased (P<0.0001) when compared with HB control and Immunosuppressed CP control group. Whereas, the DTH response was evaluated by % increase in paw edema and the results were found to be increased significantly (P<0.0005) in HB treated rats. Increase in the DTH response indicates that Health Boost has a stimulatory effect on lymphocytes and accessory cell types required for the expression of the reaction. Administration of HB at both the levels showed statistically significant (P<0.0002) increase in WBC count when compared to Cyclophosphamide treated and control treated mice. To understand the mechanism of lymphoid organs and other tissues for maintaining the strong immune system, so in the present study we also studied the effect of Health’ Boost on weight of various organs and it revealed a significant increase in Spleen (P<0.0033) and Thymus weight (P<0.0027) respectively. Further clinical studies have to be conducted to extend these results and understand the exact mechanism of bioactive molecules present in the formulation, thereby confirm its traditional use as an Immunomodulator.