Heterocyclic rings have long piqued the interest of medicinal chemists. Quinazolinone is a fused nitrogen‐based heterocyclic moiety. Some of quinazolinone derivatives have emerged as marketed drugs. A tremendous number of pharmacological activities such as anticancer, anticonvulsant, antimalarial, antifungal, antibacterial, antiinflammatory, MMP inhibitors, antidiabetic, antileishmanial, and hypolipidemic properties have been explored. A number of quinazolinone derivatives have already paved way in various stages of clinical trials. An extensive literature on developed synthetic schemes based on green chemistry and biological activities of quinazolinone has been included in this study. The content of patent filed and granted of various quinazolinone‐based compounds are also mentioned. Development in the medicinal chemistry of quinazolinone. SAR have been described. In vitro and in vivo biological activities