abstract: Mechanical properties of wheat starch film with different amount of additives: sorbitol as plasticizer and bovine serum albumin, were investigated in the simple extension test. The concentration of sorbitol in 2.5% filmogenic starch blend was 20 and 40% and the concentration of albumin was 0, 2 and 4%. The data were compared with those obtained for a commercial synthetic film based on polypropylene and polyester. Mechanical parameters: tensile strength, strain at break, stress in relative strain of 0.01 and 0.02, density of elastic energy accumulated at break and Young modulus were determined from the force-deformation curves for all the films studied. The best mechanical performance was observed for the starch films with sorbitol at 40% and albumin below 2%. The presence of globular denaturated protein in higher concentration makes it difficult for the polymer chains to form a strongly entangled network, responsible for high tensile strength.