The indolyl-4(3H)-quinazolinone core is an important structural motif in functional molecules. However, few methods exist for its direct modification, which limits its potential application. Reported herein is a palladium-mediated amination of halogen-containing indolyl-4(3H)-quinazolinones with a variety of primary and secondary amines via the corresponding palladium oxidative addition complexes. The protocol allows the facile synthesis of indolyl-4(3H)-quinazolinone derivatives with amino groups at all the positions of the benzene ring in moderate to good yields with mild reaction conditions and good functional group tolerance. Furthermore, the antitumor activity of these products was evaluated.