Visible light‐induced site‐selective C−H alkylation and alkenylation of 2‐aryl heteroarenes with maleimides at room temperature via dual catalysis in an aqueous medium has been disclosed. This operationally simple and mild approach enables the selective formation of alkylation and alkenylation products up to 92% yield under silver‐free conditions with excellent substrate scope. For the mechanistic examination, KIE, H/D labeling experiments, light on‐off experiments, and quantum yield measurements were carried out. Moreover, the present approach for the alkylation and alkenylation of 2‐aryl heteroarenes is suitable for scalable synthesis.