Copper(I)-catalyzed N-arylation (both N1- and N3-) of hydantoins with diaryliodonium salts as aryl partners at room temperature is reported. The transformation allows diverse scopes on both hydantoins and diaryliodonium salts delivering functionalized N3-arylated products under mild reaction conditions. The presence of hydrogens at C5- and N1- position of the hydantoin does not lead to other side products. Chiral hydantoins can also be synthesized via this methodology. Sterically complicated ortho-substituted diaryliodonium salts are tolerated and delivered challenging ortho-arylated products. In addition, this strategy can also be effectively extended to N1-arylation of hydantoins. © 2020 Wiley-VCH GmbH