The invention relates to an instant cheese and a preparation method thereof. The preparation method comprises the steps: using full-cream fresh milk as main material, pasteurizing the milk after being hydrolyzed through lactase, and concentrating the full-cream fresh milk to 35-40 percent of the original volume in vacuum. The preparation method of the instant cheese has the core points that transglutaminase is added at 35 DEG C, and milk proteins are linked to form a protein network under the action of the transglutaminase, thereby forming a uniform and stable gel system easily. Then, chymosin is added for promoting gel to form , and uniform, stable and delicate instant cheese can be obtained in a water bath for half hour at about 30 DEG C. The invention is simple and easy for operation, and can be used for development of various application products on the theoretical basis, including breakfast cereal cheese, jelly cheese and the like. Moreover, the instant cheese can meet the requirements of consumers for taste, texture, nutrition, and the like.