The heat-soluble aggregates were prepared by heat treatment (pH value 7.2, 100℃, 20min),and the cavitation microjet of different pressures (0, 30MPa, 60MPa, 90MPa, 120MPa) were respectively applied to the thermal aggregates. Impacts of cavitation microjet treatment on structural characteristics (3D microstructure, molecular weight distribution, functional group, particle size, potential and hydrophobicity) and emulsifying properties (emulsification and emulsion stability) of soluble rice bran protein aggregate were investigated by using soluble rice bran protein as a control. The results showed that compared with the heatsoluble aggregates, 3D microstructure height and particle size, total free sulfhydryl content, the average particle size and β-sheet content were reduced to the lowest point after cavitation microjet treatment (90MPa), and the structure became loose;the surface hydrophobicity, emulsifying property and emulsion stability reached the maximum value, which was increased by 798.05, 90.32m2/g and 281.68min, respectively, compared with the heatsoluble aggregate. Low-pressure (30~90MPa) micro-jet treatment would reduce the hotsoluble aggregate particles, convert the insoluble aggregate into soluble aggregates, and increase the emulsifying properties, while high pressure (120MPa) would cause the protein to aggregate and the emulsifying properties would be slightly reduced.