In this study, the modified sturgeon myofibrillar protein was prepared by the combination of malondialdehyde and ultrasonic induction and used as the emulsifier to form a stable high internal phase Pickering emulsion (HIPPEs) with internal phase up to 75%. The results showed that combined modification reduced the fluorescence intensity, enhanced the surface hydrophobicity, changed the secondary structure, and made the protein particles smooth. The confocal laser scanning microscopy confirmed the formation of a stable HIPPEs. The interfacial tension and rheological properties of protein stabilized HIPPEs were improved by the combined modification and the encapsulation efficiency of quercetin reached 89.32%. In vitro digestion showed that the combined modified protein-stabilized HIPPEs significantly improved the rate of lipid digestion and the bioavailability of quercetin while reducing the degradation of quercetin. The findings indicated that the utilization of modified sturgeon myofibrillar protein to stabilize HIPPEs hold significant promise for various biological applications, owing to its capacity as a carrier for the regulated discharge of bioactive agents.