The long struggle to combat and definitively eradicate the various forms of cancer that affect millions of patients worldwide is constantly being enriched with new therapeutic tools. In this challenge, many substances extracted from plants are gaining much attention, which, compared to traditional synthetic chemotherapeutics, have the advantage of a lower incidence of side effects, with the same antitumor efficacy. Among the substances of plant origin there are the Quinazolinones, from which many chemical derivatives have been synthesized, which have demonstrated a broad spectrum of therapeutic efficacy. In this work, we will review the therapeutic properties of the main Quinazolinone derivatives, and their supposed mechanism of action. They are very promising substances with positive developments in the fight against neoplastic pathology.