In view of the effective range of biological activities exhibited by quinazolinones, a series of 2, 3-disubstituted quinazolin-4-(3H)-ones have been synthesized and evaluated for analgesic, antibacterial and antifungal activities. Five derivatives of quinazolones were synthesized by incorporating the heterocyclic moieties of substituted Indole, Benzothiazole and Pyridine at third position of the ring. The structures of the compounds were confirmed on the basis of IR, 1H NMR and Mass spectroscopy. The analgesic and antimicrobial activity of the compounds was screened by Eddy’s hot plate method and Disc diffusion method respectively. All the five compounds could show analgesic and antimicrobial activities. The compound II showed better analgesic activity than other compounds. Significant activity was shown by compound IV against gram positive organisms and by compound I against gram negative organisms. The best antifungal activity was shown by compound IV.