The low solubility and high polymer quality of rice protein lead to poor emulsification performance， which limits the application of rice in food processing and delays the process of high-value utilization of rice. It is of great significance to improve the solubility and emulsification of rice protein by modifying its molecular structure. In this experiment， crushed rice was used as raw material， and pre-gelatinization， ultra-fine grinding， and ultra-fine pre-gelatinization were carried out respectively， then the structure and functional characteristics of the extracted rice protein were detected to evaluate the effect of different processing methods on the emulsifying properties of rice protein. The results showed that compared with pre-pasteurized rice protein (PRP) and ultra-micro-milled rice protein(URP)， the intensity of infrared characteristic absorption peaks of pre-pasteurized ultra-milled rice protein (PURP) increased， and the ultraviolet absorption spectra showed a blue-shift phenomenon； the synergistic technique of pre-pasteurization and ultra-micro-milling increased the total sulfhydryl group and disulfide bond contents from 19.21 and 7.53 μmol/g in RP to 24.49 and 11.36 μmol/g； the β-folding content of all four proteins ranged from 38.74% to 41.30%， with the highest ratio and stable secondary structure； and， the total sulfhydryl and disulfide bond content increased， with the highest β-folding content and stable secondary structure. The hydrophobic sites and sulfhydryl groups of the PURPs were exposed， which promoted the hydrophobic interactions and sulfhydryl group-to-disulfide bond exchange reactions， and the protein particles aggregated with each other to form a gluten-like network structure. It indicates that the synergistic technique of pregelatinized ultrafine milling improved the emulsification， emulsion stability， foaming rate， and foaming stability of rice protein， and the four properties were improved by 58.29%， 53.13%， 11.85% and 50.46%， respectively.