The manufacture of edible/biodegradable films or coatings can potentially add value to soy protein. Such films can find using as edible or nonedible food packaging materials. The effect of soy protein film-forming solutions on film formation, tensile properties of soy protein/pectin blend films were changed significantly by the amount of glycerol and the ratio of soy protein/pectin. Moreover mechanical properties of soy protein/pectin-montmorillonite clay have been studied. Tensile strength and modulus decreased as the relative humidity increased while with increasing relative humidity elongation at break increased.