The　potassium　storage　performance　of　UiO-66　derivatives　was　investigated　by　density　functional　theory　calculations.　The　calculation　results　show　that　the　substitution　of　all　Zr　in　nodes　of　UiO-66　by　Ti　reduces　the　band　gap.　During　potassiation,　UiO-66-Ti　and　UiO-66-Hf　have　similar　charge　transfer　processes　to　UiO-66,　in　which　the　charges　of　Ti　and　Hf　are　almost　not　changed,　and　the　charge　transfers　from　K　to　C　or　O　near　it.　Compared　with　UiO-66,　UiO-66-Hf　has　a　lower　theoretical　capacity　(490　mAh/g)　with　a　smaller　volume　expansion　and　a　slightly　higher　energy　barrier　for　K-ion　diffusion.　UiO-66-Ti　has　a　lower　diffusion　barrier　for　K　ion　although　it　has　a　larger　volume　expansion　with　all　sites　occupied　by　K.　For　the　−NH2,　−NO2,　−Br,　−Cl,　−OH,　−SH,　and　−CH3　functionalized　UiO-66,　the　substitutions　of　H　in　ligands　reduce　the　band　gap　of　UiO-66,　with　the　largest　reduction　in　UiO-66-NH2.　The　p　orbitals　of　N　in　the　NH2　contribute　greatly　to　the　reduction　of　the　band　gap.　The　K　intercalated　at　the　K2(L)　and　K3　sites　during　the　charging　process　will　transfer　part　of　the　electrons　to　the　substituents.　Between　the　Zr6O4(OH)4　nodes,　there　will　be　a　migration　path　that　crosses　the　substituent,　and　the　diffusion　energy　barrier　on　this　path　is　smaller　than　that　of　the　original　path　of　UiO-66.　The　results　suggest　that　proper　modification　of　UiO-66　can　improve　its　electronic　conductivity　and　ionic　conductivity　as　the　anode　of　potassium　ion　battery.　©　2022　American　Chemical　Society.