Nickel　oxide　(NiOX)　has　a　crucial　role　in　enhancing　the　efficiency　and　stability　of　p-i-n　inverted　perovskite　solar　cells　(PSCs),　which　hold　great　potential　for　commercialization.　However,　improving　contact　passivation　between　perovskites　and　NiOX　is　a　challenge　due　to　a　hindered　buried　interface.　In　order　to　address　this　issue,　self-assembled　monolayers　(SAMs)　are　introduced　as　a　buffer　layer　to　prevent　direct　contact　and　non-radiative　recombination.　While,　the　large　dipole　moment　of　SAMs　increases　the　work　function　of　NiOX,　which　is　crucial　for　enhancing　hole　transport　performance,　given　the　low　interfacial　potential　barrier　for　hole　transfer.　By　a　combination　of　the　first-principles　calculations,　drive-level　capacitance　profiling,　and　transient　absorption　spectrum　characterization,　the　understanding　of　the　ion-dipole　interactions　and　interface　passivation　mechanism　of　potassium　fluoride　(KF)　ultra-thin　buffer　layer　between　SAMs　and　perovskites　is　provided.　The　efficiency　of　inverted　PSCs　as　high　as　23.25%　is　obtained,　and　the　unencapsulated　devices　kept　90%　of　initial　efficiency　following　1400 h　aging　under　nitrogen,　which　demonstrate　remarkable　long-term　stability　as　well.　This　novel　strategy　highlights　the　significance　of　SAMs　dipole　moment　at　the　NiOX/perovskites　interface　and　provides　a　new　approach　to　address　buried　interfaces　for　high-efficiency　and　long-term　stability　in　inverted　PSCs.　©　2024　Wiley-VCH　GmbH.