Hibiscus rosa sinensis Linn. is one of the important medicinal as well as ornamental plant, belongs to family Malvaceae. It is commonly called Gurhal. The flower of Hibiscus rosa sinensis Linn. possess various activity such as anti - convulsents, antidiabetic, antipyretic, antioxidant, antifertility and antidiarrheal. IR spectroscopy of ethanolic flower extract shows the presence of functional groups like diallyl sulfoxide, sulfonamide, carbonyl, amide, gem dimethyl and flavonoids such as NaQSA [Sodium Salts of Quercetin 5^’ Sulfonic Acid], quercetin, flavone, myricetin and fisetin. This proves its correlation with antimicrobial activity.