The present study aimed to determine the effect of Lactuca sativa (lettuce) extract on alleviating Ehrlich ascites carcinoma (EAC) in female mice. EAC was induced by injection of 0.2 ml of (2.5×10⁶ tumor cells with single cells suspension) in the medial aspect of the right thigh of female albino mice, a mixture of L. sativa extract powder was supplemented at doses of (100 and 200 gm/10 kg normal ration), respectively, from the first day of experiment for 21  days. The obtained results indicated that feeding on Lettuce extract powder significant increased serum glucose, albumin and high density lipoprotein cholesterol (HDL-c) towards the normal levels. meanwhile, significant decreases triacylglycerols (Tg), total cholesterol (TC), low density lipoprotein cholesterol (LDL-c) concentrations, as well as the activity of liver enzymes involving alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and alkaline phosphatase (ALP); in addition to a significant decreasing of the tumor size were observed in EAC- L, sativa extract powder supplemented mice when compared to EAC-cells bearing mice.  From the obtained results it could be concluded that lettuce extract is a natural, cheap, less toxic vegetable with great potential therapeutic effect against Ehrlich ascites carcinoma and other complications resulted from malignant tumors.