This study introduces a novel photocatalytic doping method for organic semiconductors (OSCs) that uses air as a weak oxidant (p-dopant) and operates at room temperature. The method enables efficient doping with weak and widely available dopants, achieving electrical conductivities exceeding 3,000 S cm⁻¹. The approach involves a photocatalytic cycle where a photocatalyst (PC) is photoexcited to oxidize or reduce OSCs, with a weak dopant regenerating the PC. The method is general and applicable to various OSCs and photocatalysts, allowing for both p-doping and n-doping. The study demonstrates the successful photocatalytic reduction (n-doping) and simultaneous p-doping and n-doping of OSCs, with the organic salt used to maintain charge neutrality as the only chemical consumed. The method offers a promising approach for advancing OSC doping and developing next-generation organic electronic devices. The process is efficient, uses recyclable and air-stable PCs, and consumes only weak dopants and a salt. The study also shows that the method can be applied to a wide range of conjugated polymers, including those with different ionization potentials and hydrophilic or hydrophobic side chains. The results indicate that the method is effective for both p-doping and n-doping, enabling the simultaneous oxidation and reduction of OSCs, which is challenging with conventional doping methods. The approach has potential technological implications, such as the fabrication of thermoelectric generators with both p-type and n-type legs doped simultaneously. The study highlights the importance of photocatalytic doping for fundamental and applied research in organic electronics.This study introduces a novel photocatalytic doping method for organic semiconductors (OSCs) that uses air as a weak oxidant (p-dopant) and operates at room temperature. The method enables efficient doping with weak and widely available dopants, achieving electrical conductivities exceeding 3,000 S cm⁻¹. The approach involves a photocatalytic cycle where a photocatalyst (PC) is photoexcited to oxidize or reduce OSCs, with a weak dopant regenerating the PC. The method is general and applicable to various OSCs and photocatalysts, allowing for both p-doping and n-doping. The study demonstrates the successful photocatalytic reduction (n-doping) and simultaneous p-doping and n-doping of OSCs, with the organic salt used to maintain charge neutrality as the only chemical consumed. The method offers a promising approach for advancing OSC doping and developing next-generation organic electronic devices. The process is efficient, uses recyclable and air-stable PCs, and consumes only weak dopants and a salt. The study also shows that the method can be applied to a wide range of conjugated polymers, including those with different ionization potentials and hydrophilic or hydrophobic side chains. The results indicate that the method is effective for both p-doping and n-doping, enabling the simultaneous oxidation and reduction of OSCs, which is challenging with conventional doping methods. The approach has potential technological implications, such as the fabrication of thermoelectric generators with both p-type and n-type legs doped simultaneously. The study highlights the importance of photocatalytic doping for fundamental and applied research in organic electronics.