Beta-glucans are widely used in treatment, cosmetics, and the food industry. Glucans play a significant role in activation of the immune and antioxidant system and inhibiting tumor proliferation. In the current study the antitumor activities of new high and low molecular weight beta-glucan derived from oats were investigated in two human lung cancer cell line (A549, H69AR) and normal keratinocytes (HaCaT). The effect of high and low molecular weight beta-glucan from oat was evaluated by cellular viability assessment, lipid peroxidation and manganese superoxide dismutase evaluation and cytoskeleton visualisation. Additionally the level of red blood cells hemolysis was performed. Our results indicate strong anti-tumor properties of new beta-glucan from oat and at the same time no toxicity for normal cells.