Photoinduced nickel-catalyzed demethylative cyanation and decarboxylative cyanomethylation of aryl halides are described here. Commercially available bromoacetonitrile was found to act as an efficient cyanating reagent for the photoinduced cyanation reaction in the absence of a photocatalyst. Moreover, photoredox and nickel dual-catalyzed decarboxylative cyanomethylation of aryl halides has also been realized using cesium cyanoacetate under mild conditions. A series of aryl and benzyl nitriles bearing diverse functional groups were prepared with good to high efficiency.