The hydrodistilled essential oils from different fresh aerial parts (stems and leaves, flowers and fruits) of Prangos asperula Boiss. growing wild in Lebanon were analyzed by gas chromatography-mass spectrometry. Forty two, 46 and 4 compounds representing 75.5%, 86.9% and 99.8% of the total fresh stems and leaves, flowers and fruits oils were, respectively, identified. The main compounds characterizing these oils were nerolidol (15.2%), p-menth-3-ene (13.3%), β-myrcene (9.2%) in stem and leaves; p-menth-3-ene (14.9%), nerolidol (14.7%), β-phellandrene (7.9%) in flowers; sabinene (43.5%), β-phellandrene (36.1%), α-phellandrene (11.9%) and α-terpinene (8.3%) in fruits. The antimicrobial activity of the total essential oil evaluated by growth inhibition and MIC values revealed variable levels of susceptibility in the tested bacteria and fungi. S. aureus displayed highest sensitivity (15.06 mm, MIC 5.0 µl), followed by E. coli (11.80 mm, MIC 10.0 µl), A. fumigatus (9.16 mm, MIC 10.0 µl), T. mentagrophytes (7.3 mm, MIC 25 µl), S. enteritidis (3.8 mm, MIC 25 µl) and C. albicans (1.96 mm, MIC 50 µl). The oil displayed a remarkable activity against both S. aureus being more effective than the antibiotic Norfloxacine (10 µg) and T. mentagrophytes which was completely resistant to the antifungal Nystatine (100 µg). The findings confirm the traditional use and promising potential of the antibacterial properties of this plant oil. This opens the possibility for further research on other biocidal activities and investigations of individual antimicrobial and antifungal component.