The　Fenton　reaction,　an　effective　advanced　oxidation　process　(AOP)　for　degrading　organic　pollutants,　requires　the　addition　of　H　2　O　2　that　is　expensive　and　not　environmentally　friendly　to　some　extent.　It　has　been　reported　that　piezocatalysis　can　generate　H　2　O　2　under　mechanical　excitation.　Therefore,　it　is　promising　to　carry　out　the　Fenton　catalysis　utilizing　in　situ　H　2　O　2　generated　by　piezocatalysis.　However,　the　current　piezocatalysis-assisted　Fenton　(Piezo-Fenton)　reaction　was　realized　by　adding　piezoelectric　nanoparticles　and　Fe(II)　ions　to　pollutant　solutions,　which　would　induce　more　iron-based　chemicals　that　are　not　easy　to　recycle.　Herein,　Fe　3　O　4　-BaTiO　3　nanocomposites　were　prepared　to　demonstrate　the　feasibility　of　piezo-Fenton　catalysis　without　the　addition　of　H　2　O　2　or　Fe(II)　ions.　The　organic　dye　degradation　efficiency　of　98.2%　is　obtained　using　Fe　3　O　4　-BaTiO　3　nanocomposites　in　the　acidic　solution,　one-third　and　two-thrid　greater　than　that　of　pure　piezocatalysis　and　that　of　iron-based　Fenton　reaction,　respectively.　Moreover,　since　the　piezocatalysis　process　is　the　rate-determining　step　of　the　whole　piezo-Fenton　reaction,　all　the　H　2　O　2　generated　can　be　consumed.　Considering　that　the　solid　nanocomposites　can　be　magnetically　recycled,　piezo-Fenton　catalysis　leaves　no　additional　chemicals　in　clean　water　and　thus　provides　an　environmentally　friendly　and　low-cost　approach　for　organic　dye　degradation.