Herein,　a　series　of　N-TiO2/Ti3C2　(N-TTCx)　composites　are　constructed　via　ultrasonically　treating　pre-synthesized　N　doped　TiO2　and　Ti3C2　at　room　temperature.　The　intimate　contact　between　N-TiO2　and　Ti3C2　is　verified　by　the　transmission　electron　microscopy,　scanning　electron　microscopy,　and　X-ray　photoelectron　spectroscopy.　And,　the　N-TTC0.06　composites　exhibit　the　best　sonophotocatalytic　performance,　which　is　1.9　times　and　8.8　folds　higher　than　that　of　TiO2　for　pollutant　degradation　and　nitrogen　fixation,　respectively.　What＇s　more,　sonophotocatalytic　degradation　of　pollutants　and　nitrogen　fixation　shows　larger　efficiency　compared　with　that　of　photocatalysis　and　sonocatalysis,　which　is　attributed　to　the　synergistic　effect　between　sonocatalysis　and　photocatalysis　in　the　sonophotocatalytic　process.　Moreover,　taking　N-TTC0.06　for　example,　the　three　cycles　of　sonophotocatalytic　degradation　of　Rh-B　and　nitrogen　fixation　as　well　as　the　unchanged　X-ray　diffraction　before　and　after　sonophotocatalytic　nitrogen　fixation　all　confirm　the　stable　sonophotocatalytic　behavior　of　N-TiO2/Ti3C2　composites.　The　improved　sonophotocatalytic　activity　is　attributed　to　the　decrease　of　band　gap　by　N　2p　doping　level　and　the　separation/transfer　improvement　of　photoinduced　carriers　by　Ti3C2,　which　are　demonstrated　by　UV–vis　absorption　spectra,　photoelectrochemical　tests,　Nyquists　plots,　and　Mott-schottky　plots.　This　study　confirms　that　the　designed　N-TiO2/Ti3C2　composites　exhibit　great　potential　application　in　sonophotocatalytic　pollutant　degradation　and　nitrogen　fixation.　©　2021　Elsevier　B.V.