Quinazolines and its derivatives represent one of the most active classes of compounds, which possess wide range of biological activities like anti-bacterial, analgesic, anti-microbial, anti-inflammatory, anticancer, and anti-hypertensive ,antifungal, anti-HIV, antioxidant, analgesic, anticonvulsant, antimalarial, antitumor, anti-tubercular activities. The objective of the present study was to synthesize these quinazolinone derivatives 6-iodo-2-methyl-4H-benzo[d]-[1,3]-oxazin-4-one and 3-amino-6-iodo-2—methyl-3H-quinazolin-4-one and evaluate them for their antibacterial activity. 6-lodo-4H-benzoxazin-4-one was synthesized by the reaction of 2-amino-5-Iodomethylbenzoat and acetic anhydride which reacted with nitrogen nucleophile, namely hydrazine hydrate to obtain 3-amino-6-iodo-2-methyl-3H-quinazolin-4-one. The structures of the compounds were confirmed with Infrared Spectra, Proton Nuclear Magnetic Resonance, Carbon thirteen Nuclear Magnetic Resonance, mass spectra and elemental analysis. These compounds were screen for their antibacterial activities against a number of microorganisms, Escherichia coli, Klebsiella pneumonia, Bacillius species, Staphylococcus aurous, Pseudomonas aeruginosa and Candida albican. The test investigated compounds exhibited significant antibacterial activity against the bacteria when compared with the control test sample. For the IR spectra, compound 1 were characterized by absence of υ NH2and presence of υ C-O stretch in 1159 cm-1 region of the compound. Compound 2 was characterized by absence of υ C-O and presence of υNH2 in 3284 cm-1and 3194 cm-1 region of the compound. The compounds synthesized exhibited promising antibacterial activities against Staphylococcus aureus, Bacillus species and Pseudomonas aeruginosa, stock cultures. The compounds have high activity against the microorganisms. Compound 2 has a higher activity against Pseudomonas aeruginosa compared to compound 1.