The present work has been carried out to annotate the ameliorative effect of methanolic extract of leaves of Murraya koenigii in Azathioprine induced immunosuppression in mice. Healthy Swiss albino mice of either sex were divided into six groups (n=6). The control group of animals received 1% CMC solution as vehicle. AZP 50mg/kg b.w i.p was administered to animals in second group that served as disease control group. Levamisole was used as standard drug that was administered to group III at a dose of 50mg/kg b.w p.o. Groups IV, V, VI were given with 250, 500 & 750 mg/kg b.w of the extracts p.o. after the treatment period, Immunomodulatory activity of Murraya koenigii was evaluated by Delayed Type Hypersensitivity reaction, hematological parameters, Phagocytic index and determination of organ weights. Intraperitoneal administration of Azathioprine caused myelosupression and compromised immune responses. Methanolic extract of Murraya koenigii significantly increased DTH response when compared to control and disease control group. The extract also increased the Phagocytic index, WBC count and % neutrophills in a dose dependent manner. The obtained results were comparable with that of the standard drug Levamisole. The findings demonstrate that MK is a promising drug with a potent therapeutic value in stimulating the suppressed or weakened immune responses in laboratory animals and hence can act as a potent immunomodulator.