The effect of four different cooking methods（boiling， steaming， microwaving， frying） on the texture and in vitro simulated digestion of recombinant fish steaks， the cooking method and glutamine transaminase enzyme influence the texture and the in vitro simulated digestibility of recombinant fish steaks. The results showed that different cooking methods and enzyme affect the hardness， springiness， adhesiveness and chewiness of the recombinant fish steaks in varying degrees. The samples with glutamine transaminase enzyme showed an increasing trend except for cohesiveness. The cooking method and enzyme will affect the in vitro digestibility of the recombinant fish steaks， which has less influence during the mouth digestion process. Pepsin and trypsin action sites change during pepsin and gastrointestinal digestion， and digestibility is greatly affected. From the High Performance Liquid Chromatography and SDS-PAGE patterns， observed the changes in the degree of molecular separation and changes in molecular weight during the entire digestion process. This study provided a theoretical basis for the production and cooking methods of recombinant grass carp steaks.