The　efficiency　of　perovskite　solar　cells　(PSCs)　has　achieved　the　milestone　of　25%　with　a　high　speed　over　the　past　decade.　However,　miscellaneous　defects　at　grain　boundaries　and　interfaces　have　significantly　influenced　the　durability　and　efficiency　of　PSCs.　In　this　work,　D131　dye,　an　indoline　molecule　with　a　Donor-Acceptor　structure,　has　been　introduced　into　a　perovskite　precursor　as　an　additive　for　the　first　time.　The　terminal　cyanoacrylic　acid　group　of　D131　with　intense　negative　charges　can　interact　with　Pb2+　in　the　precursor　to　retard　crystallization　and　enhance　crystallinity.　Moreover,　the　D131　molecule　can　stably　passivate　the　undercoordinated　Pb2+　defects　at　grain　boundaries　and　enhance　the　thermal　and　humid　stability　of　perovskite　films.　As　a　result,　a　photovoltaic　conversion　efficiency　(PCE)　up　to　21.38%　(18.55%　for　1　cm2　active　area　device)　has　been　achieved　for　the　cell　with　the　D131　additive,　and　the　nonencapsulated　cell　can　retain　over　81%　of　its　initial　PCE　after　1100　h　of　storage　(25　°C,　15　±　5%　relative　humidity),　thus　providing　a　new　strategy　for　durable　and　high-performance　PSCs.　©　2022　American　Chemical　Society.