Abstract: The effects of heat treatment, glycosylation modification, ultrasonic modification, ultrasonic pretreatment with glycosylation modification and in vitro digestion after composite modification on the immunogenicity and functionality of egg white powder were studied. The results showed that compared with the original sample, the immunogenicity caused by egg white powder increased after heat treatment, the maximum increased was 12.77%. Compared with the heat treatment sensitization increased to a greater degree after ultrasonic modification, the maximum increased was 20.84%. Sensitization of egg white powder reduced to some extent after glycosylation modification, the maximum reduction was 29.08%. However, sensitization occurred a greater decrease after composite modification, the maximum reduction was 43.9%, sensitization further reduced after composite modified simulated digestion in vitro, the maximum reduction was 52.76%. At the same time, the functionality of egg white powder could not improve through the heat treatment effectively, while the ultrasonic treatment could effectively improved the emulsifying properties. The functionality of solubility, emulsification and antioxidant activity was improved in different degree by glycosylation modification, the functionality was improved greatly after composite modification, and the antioxidant activity was significantly enhanced after digested. This showed that the composite modification could improve the quality of products more comprehensively and more effectively, and could still maintain or even improve after digestion.