The light-promoted, nickel-catalyzed hydrogen-evolution C(sp3)-H acylation of simple alkanes with aromatic aldehydes has been achieved without the need for additional photosensitizers or oxidants. This reliable and atom-economical reaction afforded a broad range of aryl alkyl ketones in good yields, with H2 as the sole byproduct. It was successfully demonstrated on a gram scale as well as for the postfunctionalization of drug molecules. Aromatic aldehydes play multiple roles, including a photosensitizer, a coupling partner, and a hydrogen atom transfer agent.