The　physiochemical　properties,　structure　characteristics,　oxidation,　and　emulsifying　properties　of　myofibrillar　proteins　(MPs)　in　low　salt　solution　after　treated　by　the　ultrasound　were　investigated.　The　solubility,　mean　diameters,　sulfhydryl　content,　and　carbonyl　contents　of　MPs　after　ultrasonic　treatment　increased,　while　the　turbidity　decreased.　The　surface　hydrophobicity　of　MPs　with　200　W-600　W　treatment　increased,　but　decreased　at　800　W　treatment.　The　circular　dichroism　analysis　revealed　that　alpha-helix　content　increased,　while　beta-sheet　and　random　coil　content　decreased　after　ultrasonic　treatment.　Fluorescence　spectroscopy　indicated　the　fluorescence　intensities　of　MPs　were　increased　after　ultrasonic　treatment.　SDS-PAGE　results　showed　more　protein　polymers　due　to　myosin　heavy　chain　(MHC)　aggregation　via　disulfide　bonds.　Based　on　LC-MS/MS　result,　the　myosin　heavy　chain　was　susceptible　to　oxidation,　with　monooxidation　being　the　main　oxidative　modification.　Finally,　the　emulsions　stabilized　by　ultrasonically　treated　MPs,　especially　those　treated　at　800　W,　exhibited　decreased　particle　size,　improved　uniformity,　and　enhanced　stability.