Promising antimicrobial and antifungal activities have been reported in many substituted quinazoline derivatives. Earlier, Quinazoline-4-ones has been a subject of extensive pharmacological evaluation, as well as, toxicological studies for antimicrobial and antifungal activities. Its 4- chloro analog has recently revealed much superior activity to it. Scientific research and clinical studies have already documented the value of Quinazoline-4-ones in treating various microbial diseases. With this rationale, the synthesis and biological evaluation of new 4, 6- disubstituted quinazoline derivatives was undertaken through various synthetic routes. The newly synthesized derivatives have been characterized through chromatography & physical constant determination. The newly synthesized derivatives were evaluated for their antimicrobial activity against E.coli & S. aureus & for antifungal activities against candida albicans and found promising antimicrobial and antifungal activities.