Abstract: Probiotic bacteria are considered beneficial microorganisms and have been widely used. They protect against harmful bacteria that can cause diseases. This study was carried out to evaluate the potential for L. acidophilus intact cells and cell lysates as antioxidant activities and also to evaluate the potential of this bacteria and their exopolysacchariedes (EPS) as antitumor activity in vitro and in vivo against Ehrlich Ascites Carcinoma (EAC) cell line. Lactobacillus acidophilus demonstrated having antioxidant activities for both cell lysates and intact cells with increasing antioxidative properties for cell lysates against 2, 2--diphenyl-1-picrylhydrazyl (DPPH), also resistance to hydrogen peroxide and hydroxyl radical. The EPS produced by L. acidophilus showed a powerful antitumor effect in vivo and in vitro in comparison with L. acidophilus itself while, E. coli increasing solid tumor volume than control.