The invention relates to preparation methods of fermenting a Korean traditional soybean cake or a leaven. A small-sized soybean cake is formed by means of mycete and composite bacterial strains with a preparation period being shortened via automated technology. More concretely, the invention provides preparation methods of fermenting the traditional soybean cake or the leaven. The method comprises following steps of cooling cereal raw materials containing soybeans after being stewed, inoculating mycete and bacteria to be formed at certain sizes and fermenting mycete and bacteria. Furthermore, the invention also provides a preparation method of Korean traditional sauce or soy. The preparation method comprises following steps of mincing the fermented soybean cake and then pickling the fermented soybean cake in saline water after being crushed, separating the fermented soybean cake from the saline water, and carrying out curing operation. A preparation method of the traditional sauce or soy which curing operatio
