The Solanum xanthocarpum is a plant, which is used, in herbal preparations, as anti-asthmatic, anti-cough, and in the treatment of arthritis. Suppression & retention of urine, fever etc. was investigated for its immunostimulant activity. The ability of Solanum xanthocarpum ethanolic extract to give anti stress (adaptogenic) effect has showed significant increase in the duration of swimming (in treated group) as compared to the control group. The control group rats treated group of rats swam for 80.66 min (mean) where us the drug treated group of rats swam for 139.66 min. The drug treated rats showed significant increase in swimming time and registered an increase in swimming time of more than 59 min (total) over the control group. Similarly ethanolic extract of Salanum xanthocarpum was subjected for another test i.e. milk induce leucocytosis by giving S.C. Inj. of milk in doses of 4 ml/kg. Body weight produced a marked and significant increase in the leucocytes count after 24 hour of its administration. After given the ethonolic extract of Solanum Xanthocarpu, it was seen that the average leucocyte count was markedly reduced from 13883 to 1055.6. The preliminary results clearly indicate that leucocytosis induced by milk inj. was significantly inhibited by prior treatment of rats with ethanolic extract of Solanum xanthocarpum in the doses of 100 mg/ kg I.P. in 2% PVP solution.