A degradable starch/lignin blend film was prepared using corn starch and sodium lignosulfonate via a casting and solvent evaporation method. The effect of sorbitol content on the swelling properties of starch/lignosulfonate blend films was investigated. The effect of lignosulfonate content on the swelling and mechanical properties was also studied. The results showed that when the mass ratio of sorbitol to starch changed over a wide range, from 0:9 to 9:9, the water absorption of the blend films increased at first and then decreased. When the mass ratio of lignosulfonate to starch changed in the same range, the ultimate stress of the blend films decreased markedly, while the water absorption and elongation at break did not show any regular pattern. When the mass ratios of sorbitol to starch and lignosulfonate to starch were both 6:9, the resultant film presented good elasticity and improved hydrophobicity compared to those without lignosulfonate.