The new biomaterials were produced by soy protein isolate (SPI) as base material. The effects of film property such as film integrity, thickness, light transmittance, water soluble, water vapor permeability (WVP) and oil permeability (PO) were investigated by film forming conditions included SPI content, ethanol content, plasticizer (glycerol), reducing agents (Na₂SO₃), temperature, pH value of film-forming reagent and medium. With more addition of SPI concentration between 2% to 6%, it was more likely to form film, while the thickness, WVP, and PO of films increased and the film became dark. With no more than 2% addition of glycerol, the flexibility of film could be improved, but its WVP and PO were reduced. With the addition of 5% alcohol, the WVP and PO of films were also reduced. The addition of 0.1% Na₂SO₃ could improve the color of the film and reduce its PO at the same time. It could reduce the WVP and PO of the films by increasing the processing temperature and pH value of solution to a certain extent.