Rosemary (Rosmarinus officinalis L.) is one of the most economically important species of the family Lamiaceae. Rosemary extract was examined by applying 2.2-diphenyl-1- picrylhydrazyl (DPPH) radical-scavenging assays. The result proved that rosemary extract had a higher antioxidant activity by absorption at a wavelength of 517a nm by using three different concentrations (0.5, 1.0 and 3) mg/ml which performed the absorbance at (2. 314, 0. 211 and 0.296) nm in comparison with control (21.8, 92.2 and 90) nm respectively. Results obtained using chemical detection of the phytochemicals indicated the presence of flavonoids, phenols, saponins, Steroids and cardiac in rosemary water extract. Water extracts of R. officinalis leaves were investigated for their antimicrobial activity. Checker box method was used to estimation the minimum inhibitory concentrations (MIC) against Gram-positive bacteria and Gram-negative bacteria. The results showed the gradual concentration of the extract from the top to the bottom and the change of colors (pink to blue ) according to the presence of bacterial growth. Rosemary extracts showed inhibitory effect for some species bacteria by estimation minimum inhibitory concentrations (MIC) against Gram-positive bacteria and Gram-negative bacteria. The study indicates that higher concentrations of the extract were required to inhibit the bacteria. Result of inspection by digging on the culture media was more effective than using the plates
