Significant　progress　has　been　made　in　fabricating　porous　scaffolds　with　ultrafine　fibers　for　tissue　regeneration.　However,　the　lack　of　noninvasive　tracking　methods　in　vivo　makes　it　impossible　to　track　the　fate　of　such　scaffolds　in　situ.　The　development　of　near-infrared　region　II　(NIR-II,　1000-1700　nm)　dyes　provides　the　possibility　of　performing　noninvasive　visualization　with　deep-tissue　penetration　and　high　spatial　resolution　in　vivo.　Herein,　we　developed　a　polycaprolactone　(PCL)　ink　containing　the　small　organic　NIR-II　dye　SY-1030　and　the　fluorescently　labeled　macromolecular　dye　SY-COO-PCL　and　fabricated　high-resolution　NIR-II　active　scaffolds　via　electrohydrodynamic　jet　(EHDJ)　printing.　All　printed　scaffolds　subcutaneously　implanted　in　mice　were　clearly　imaged　one　week　after　the　operation.　Compared　with　scaffolds　containing　SY-1030,　the　fluorescence　intensity　emitted　from　scaffolds　containing　SY-COO-PCL　can　be　tracked　for　up　to　three　weeks.　Moreover,　the　image　quality　can　be　optimized　by　adjusting　the　dye　concentration,　laser　power,　and　exposure　time.　The　advantage　of　such　NIR-II　active　scaffolds　is　evidenced　by　the　lower　dye　concentration,　longer　tracking　period,　and　better　in　vivo　stability.　We　also　demonstrated　the　biocompatibility　and　biodegradability　of　the　scaffolds　containing　SY-COO-PCL　over　a　3-month　period.　The　developed　NIR-II　active　scaffolds　have　potential　applications　in　biopolymer　implant　tracking,　tissue　reconstruction　monitoring,　and　target-position-based　drug　delivery.　©　2021　American　Chemical　Society.　All　rights　reserved.