Anti-tumor activity of Euphorbia hirta (50 mg/kg and 100 mg/kg) has been evaluated againstEhrlich’s ascites carcinoma (EAC) in Swiss albino mice. Intraperitoneal (i.p) administration ofEuphorbia hirta was effective in reducing solid tumor mass development induced by EAC cells. Itexhibited significant anti-tumor activity in mice, when used at the dose of 100 mg/kg/day i.p., for14 days. The administration of Euphorbia hirta (100 mg/kg/day i.p.) resulted in an increase (P < 0.001) of thelife span (59.9%) of ascites tumor bearing mice as compared to the control group. After 14 days,on developed tumor masses, Euphorbia hirta administration brought about significant reduction intumor volume and it reverse the changes in the hematological parameters, responding to tumorinoculation. The results are indicative of the anti-tumor activity of Euphorbia hirta against EACinduced tumor in a dose dependent manner.