Diazo compounds have been employed as the nucleophile in a silver-catalyzed three-component reaction with amines and 2-alkynylbenzaldehydes. Various 3-benzazepines were prepared in a one-pot manner based on a cascade imine--yne cyclization/nucleophilic addition/1,2-aryl migration process. Moreover, this Ag(I)-mediated reaction also provides a practical route to diazo-containing dihydroisoquinolines under slightly modified conditions.