A simple protocol for the synthesis of quinazoline-4(3H)-ones by tandem cyclization of 2-halobenzoic acids with amidines has been developed by using KOH as a base in DMSO at 120 °C. This protocol does not involve the use of any transition-metals or ligands or any coupling reagents. The present methodology is operationally simple, scalable and varieties of quinazolinone derivatives were obtained in good to excellent yields.