Soybean composition, which is different from those of other beans and grains, gives from 35 to 40 percent protein, 15 to 20 percent oil, and 20 to 25 percent sugar. Soybean has been extensively used as the raw material for traditional foods such as bean curd, soy sauce, soy paste and so on, since ancient times in Korea. Ultracentrifugal components of the soybean proteins represent four major peaks with sedimentation constants of about 2, 7, 11 and 15S. The two major reserve protein of soybean, 7S and 11S globulins, have been isolated and characterized by many works. The curd made with microbial enzyme exhibited minuter structure than those of the metal ion-and acid-treatment. Thus, the curd obtained by enzymatic operation serves as a material for further development of food items, and the procedure may by widely applicable in food processing.