Potassium-ion　hybrid　capacitors　(PIHCs)　hold　the　advantages　of　high-energy　density　of　batteries　and　high-power　output　of　supercapacitors　and　thus　present　great　promise　for　the　next　generation　of　electrochemical　energy　storage　devices.　One　of　the　most　crucial　tasks　for　developing　a　high-performance　PIHCs　is　to　explore　a　favorable　anode　material　with　capability　to　balance　the　kinetics　mismatch　between　battery-type　anodes　and　capacitor-type　cathode.　Herein,　a　reliable　route　for　fabricating　sulfur　and　nitrogen　codoped　3D　porous　carbon　nanosheets　(S-N-PCNs)　is　reported.　Systematic　characterizations　coupled　with　kinetics　analysis　indicate　that　the　doped　heteroatoms　of　sulfur　and　nitrogen　and　the　amplified　graphite　interlayer　can　provide　ample　structural　defects　and　redox　active　sites　that　are　beneficial　for　improving　pseudocapacitive　activity,　enabling　fast　kinetics　toward　efficient　potassium-ion　storage.　The　S-N-PCNs　are　demonstrated　to　exhibit　superior　potassium　storage　capability　with　a　high　capacity　of　107　mAh　g−1　at　20　A　g−1　and　long　cycle　stability.　The　as-developed　PIHCs　present　impressive　electrochemical　performance　with　an　operating　voltage　as　high　as　4.0　V,　an　energy　density　of　187　Wh　kg−1,　a　power　density　of　5136　W　kg−1,　and　a　capacity　retention　of　86.4%　after　3000　cycles.　©　2019　WILEY-VCH　Verlag　GmbH　&　Co.　KGaA,　Weinheim