The　design　of　high-performance　stretchable　n-type　semiconductors　is　important　in　the　construction　of　complementary　circuits　for　flexible　electronics.　Herein,　we　propose　a　strategy　by　blending　an　electron　transport-conjugated　polymer　poly(7,7′-difluoro-N,N′-bis(6-(trioctylsilyl)hexyl)-isoindigo-alt-(E)-1,2-bis(3,4-difluorothien-2-yl)ethene)　(IID-SiC8)　with　a　hole　transport　elastic　block　copolymer　poly[2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene]-block-hydrogenated　hydroxyl-terminated　polybutadiene　(PBTTT-b-HTPB)　to　achieve　stretchable　semiconductors　with　high　electron　mobility　and　synaptic　function　in　organic　thin-film　transistors.　The　p-type　segments　of　PBTTT-b-HTPB　behave　as　trap　centers　for　minority　holes　to　improve　the　overall　performance　of　n-channel　transistors　or　function　as　hole-trapping/detrapping　sites　to　create　memory　windows,　depending　on　the　blending　ratio.　By　adding　25　wt　%　PBTTT-b-HTPB,　the　blend　film　exhibits　mobility　up　to　1.71　cm2　V-1　s-1,　which　is　the　highest　value　of　n-type　stretchable　semiconductors　so　far,　together　with　a　high　on/off　ratio　of　106-107.　Notably,　the　mobility　of　the　nanofilm　remains　almost　unchanged　after　1000　stretching　cycles　under　100%　strain　due　to　good　fatigue　resistance.　By　adding　75　wt　%　PBTTT-b-HTPB,　synaptic　functions　were　realized　as　a　response　to　gate　voltage　pulse.　Neuromorphic　computing　simulation　constructed　with　this　synaptic　transistor　can　conduct　pattern　recognition　at　high　accuracy　up　to　85.00%.　Our　multipurpose　strategy　of　employing　a　single　matrix　that　can　simultaneously　tune　mechanical　properties　and　electrical　functions　offers　the　prospect　of　high-performance　stretchable　functional　optoelectronic　devices.　©　2023　American　Chemical　Society.