The present study was investigating experimentally the possible antitumor effects of aqueous extract of Biophytum sensitivum Linn (AEBS) leaves against Dalton’s Ascitic Lymphoma (DAL) bearing Swiss albino mice. The AEBS administered orally at the doses of 100 and 200 mg/kg b. wt, in mice for 28 days after 24 h of tumor inoculation. The effects AEBS on the growth of murine tumor, life span of DAL bearing mice were studied. Treatment with AEBS decreased the tumor volume and viable cell count there by increasing the life span of DAL bearing mice. The present work indicates that the aqueous extract of B. sensitivum exhibited significant antitumor activity.