The present study aimed to evaluate the anti-bacterial activities (in vitro) of the total extract of 70% methanol and successive extractsof different organic solvents  (petroleum ether, chloroform, methanol, 50% methanol extracts),  and their isolated compounds of the vegetative parts and flowers of Phlomis floccosa against Escherichia coli, Klebsiella pneumonia, Proteus spp.andStaphylococcus aureus. Where the best antibacterial active extract for vegetative parts was chloroform, while it was petroleum ether extract for flowers. Isolation and purification of the major compounds of the active fractions concluded that, 7, 3', 4'-trimethoxy quercetin (flavonoid) and hahnfett (hydrocarbon) were detected in the vegetative parts, meanwhile, stewertiisin B (sesquiterpene) was detected in the flowers. The three isolated compounds showed active inhibition of the bacterial growth.