The immunosuppressive activity of the Methanol extract of bark of Madhuca longifolia (Koenig)consisting of a mixture of saponins, flavonoids, tannins, steroids, phenol and glycosides wasstudied on the immune responses in mice. Methanol extract of Madhuca longifolia (MLL) wasadministered orally at doses of 50, 100 and 150 mg/kg/day to healthy mice divided into fourgroups consisting of six animals each. The assessment of immunomodulatory activity was carriedout by testing the humoral (antibody titre) and cellular (foot pad swelling) immune responses tothe antigenic challenge by sheep RBCs. Furthermore, the effect on hematological parameters aswell as relative organ weight was determined. On oral administration MML showed a significantdecrease delayed type hypersensitivity (DTH) response whereas the humoral response to sheepRBCs was unaffected. Thus MLL significantly suppressed the cellular immunity by decreasingthe footpad thickness response to sheep RBCs in sensitized mice. With a dose of 100 and 150 mg/kg/day the DTH response was 7.66 ± 2.75 and 6.41 ± 1.21 respectively in comparison to correspondingvalue of 14.50 ± 2.38 for untreated control group. These differences in DTH response werestatistically significant (P < 0.05). The study demonstrates that MLL shows preferential suppression of thecomponents of cell-mediated immunity and shows no effect on the humoral immunity.