Peroxygenases are very promising catalysts for oxyfunctionalization reactions. Their practical applicability, however, is hampered by their sensitivity against the oxidant (H₂O₂), therefore necessitating in situ generation of H₂O₂. Here, we report a photoelectrochemical approach to provide peroxygenases with suitable amounts of H₂O₂ while reducing the electrochemical overpotential needed for the reduction of molecular oxygen to H₂O₂. When tethered on single-walled carbon nanotubes (SWNTs) under illumination, flavins allowed for a marked anodic shift of the oxygen reduction potential in comparison to pristine SWNT and/or nonilluminated electrodes. This flavin-SWNT-based photoelectrochemical platform enabled peroxygenases-catalyzed, selective hydroxylation reactions.