Black　phosphorus　(BP)　nanosheets　with　unique　biocompatibility　and　superior　optical　performance　have　attracted　enormous　attention　in　material　science.　However,　their　instability　and　poor　solution-processability　severely　limit　their　clinical　applications.　In　this　work,　we　demonstrate　the　use　of　silk　fibroin　(SF)　as　an　exfoliating　agent　to　produce　thin-layer　BP　nanosheets　with　long-term　stability　and　facile　solution-processability.　Presence　of　SF　prevents　rapid　oxidation　and　degradation　of　the　resultant　BP　nanosheets,　enhancing　their　performance　in　physiological　environment.　The　SF-modified　BP　nanosheets　exhibit　subtle　solution-processability　and　are　fabricated　into　various　BP-based　material　formats.　As　superior　photothermal　agents,　BP-based　wound　dressings　effectively　prevent　bacterial　infection　and　promote　wound　repair.　Therefore,　this　work　opens　new　avenues　for　unlocking　current　challenges　of　BP　nanosheet　applications　for　practical　biomedical　purposes.　©　2018　American　Chemical　Society.