This research aims to understand the effect of Lactobacillus rhamnosus GG fermentation on egg white powder. In this study, some physico-chemical, functional, textural, and protein structure properties of microwave (MD) and oven dried (OD) egg white powders were determined. The fermentation process decreased the pH value (5.92, 5.82) and foaming capacity (20.83%, 27.20%) of MD and OD groups. The highest yield (11.61%) and emulsion capacity values (78.17%) were observed in fermented oven dried group. While MD group (703.22 g) had the lowest hardness value, OD group (3301.35 g) exhibited highest hardness value. The denaturation peaks of the samples were ranged between 61.00 °C and 80.43 °C. Scanning electron microscopy images of all sample groups showed broken glass structure. This study suggests that fermentation (L. rhamnosus GG) can effectively improve the quality properties of egg white powder and thus fermented egg white powders could be used in the food industry. Graphical abstract: [Figure not available: see fulltext.]