A　3D　macroporous　stainless　steel　fiber　felt　(SSFF)　is　used　as　base　material　and　a　simple　water　bath　method　is　adopted　to　directly　load　Pd　nanocatalysts　on　SSFF　to　fabricate　the　air　cathode　of　microbial　fuel　cells　(MFCs).　The　optimum　Pd　loading　is　explored　on　the　basis　of　the　optimized　PVP　additive　amount　and　reaction　temperature.　To　attain　a　high　ORR　activity,　a　conductive　carbon　black　filling　layer　is　added　into　the　3D　pores　of　Pd-SSFF.　A　series　of　physical　and　electrochemical　tests　are　conducted　to　characterize　the　morphology,　chemical　composition　and　oxygen　reduction　activity　and　then　the　obtained　cathodes　are　installed　in　MFCs　for　electricity　production　verification.　The　results　show　that　the　Pd-SSFF　cathode　at　a　Pd　loading　of　0.5　mg　cm(-2)　(Pd-SSFF-0.5)　achieves　high　output　voltage　and　power　density　(492.65　mV,　390.79　mW　m(-2))　which　are　comparable　to　the　conventional　Pt/C　electrode　(504.80　mV,　405.47　mW　m(-2)).　Furthermore,　with　Pd-SSFF-0.5　cathode　the　high-voltage　platform　duration　of　MFC　in　one　operation　cycle　is　2.79　times　of　that　of　Pt/C　electrode.　Excellent　mechanical　properties　(high　pressure　and　corrosion　tolerance),　high　electric　energy　output　and　simple　fabrication　prove　it　is　an　efficient　strategy　to　improve　the　overall　performance　of　MFCs　using　the　obtained　cathodes.　(C)　2019　Elsevier　Ltd.　All　rights　reserved.