A new series of quinazolinone-containing silver N-heterocyclic carbene (NHC) complexes have been synthesised by combining the appropriate N-substituted imidazolium salt with silver oxide in DCM. The proposed structures for the novel compounds have been confirmed by 1H-NMR,13C-NMR, FT-IR. To assess their antimicrobial efficacy against gram-negative E. coli and gram-positive S.aureus bacterial strains as well as C.albicans fungal species, their Minimum Inhibition Concentration (MIC) values have been determined. Among the novel synthesized analogues moderately active derivatives were P-3a, P-3d, P-4a and P-4d found effective on species S.aureus, B.subtilus,P.aeruginosa and E. coli also found effectiveness on species C. albicans, A. niger.These findings indicated all of the substances inhibited the growth of all bacterial and fungal strains and several complexes had good antimicrobial effects.The increasing applications of ILs in the pharmaceuticals and new drug development fascinating researchers in recent years. This research covers the medical and pharmacological approach, as well as other significant applications of ILs in a variety of sectors.