Abstract: In order to improve the stability of protein-based nanoemulsion, the soy protein isolate (SPI)-galactooligosaccharide (GOS) conjugate obtained by wet glycation was used as the emulsifier to prepare the nanoemulsion. By determining the intermediate product, the degree of browning, and the functional characteristics and molecular weight distribution of the SPI during the reaction process, the glycation products of different reaction stages were selected to prepare nanoemulsions. Then, according to the average particle size and particle size distribution of the nanoemulsion in different processing environments, the influence of glycation reaction on the stability of the SPI nanoemulsion system in different processing environments was analyzed. The results showed that as the reaction time increases, the grafting degree of SPI and GOS gradually increased, and the intermediate products and browning degree of Maillard reaction both increased first and then stabilized; the solubility and emulsification of SPI after glycation significantly improved; SDS-PAGE results showed that SPI and GOS formed macromolecular polymers through glycation reaction. The analysis results of the particle size and stability of the nanoemulsion showed that compared with the nanoemulsion stabilized by SPI alone, the average particle size of the emulsions stabilized by the conjugates were significantly reduced, the absolute value of the zeta potential was significantly increased, and the particle size distribution was more uniform, and the acid, heat and salt ion stability were higher.