Currently,　high-performance　polymerized　small-molecule　acceptors　(PSMAs)　based　on　ADA-type　SMAs　are　still　rare　and　greatly　demanded　for　polymer　solar　cells　(PSCs).　Herein,　two　novel　regioregular　PSMAs　(PW-Se　and　PS-Se)　are　designed　and　synthesized　by　using　centrosymmetric　(linear-shaped)　and　axisymmetric　(banana-shaped)　ADA-type　SMAs　as　the　main　building　blocks,　respectively.　It　is　demonstrated　that　photovoltaic　performance　of　the　PSMAs　can　be　significantly　improved　by　optimizing　the　configuration　of　ADA-type　SMAs.　Compared　to　the　axisymmetric　SMA-based　polymer　(PS-Se),　PW-Se　using　a　centrosymmetric　SMA　as　the　main　building　block　exhibits　better　backbone　coplanarity　thereby　resulting　in　bathochromically　shifted　absorption　with　a　higher　absorption　coefficient,　tighter　interchain　π–π　stacking,　and　more　favorable　blend　film　morphology.　As　a　result,　enhanced　and　more-balanced　charge　transport,　better　exciton　dissociation,　and　reduced　charge　recombination　are　achieved　for　PW-Se-based　devices　with　PM6　as　polymer　donor.　Benefiting　from　these　positive　factors,　the　optimal　PM6:PW-Se-based　device　exhibits　a　higher　power　conversion　efficiency　(PCE)　of　15.65%　compared　to　the　PM6:PS-Se-based　device　(8.90%).　Furthermore,　incorporation　of　PW-Se　as　a　third　component　in　the　binary　active　layer　of　PM6:M36　yields　ternary　devices　with　an　outstanding　PCE　of　18.0%,　which　is　the　highest　value　for　PSCs　based　on　ADA-type　SMAs,　to　the　best　of　the　knowledge.　©　2024　Wiley-VCH　GmbH.