Abstract:The content of the extracts obtained from Lavandula angustifolia, which were grown in Burdur Örtülü locality, was determined via HPLC and GC-MS analysis and the anti-microbial effect of the essential oil L. angustifolia was also investigated. The dried flowers of L. angustifolia were extracted and the essential oil was distilled from the remaining part. Various phenolic compounds in the extract were quantitatively determined by HPLC. Quantitatively caffeic acid, rosmarinic acid, and 4-hydroxybenzoic acids were the most abundant phenolic acids in the content in decreasing order. 31 different compounds were determined by GC-MS analysis: Linalool and linalyl acetate have the highest concentration. Anti-microbial effects of the essential oil of L. angustifolia were determined against the most frequently encountered microorganisms in the cosmetics: Candida albicans, Staphylococcus aureus, Pseudomonas aeruginosa, and Aspergillus brasiliensis. It was observed that the essential oil L. angustifolia could completely remove the contamination caused by the microorganisms as of the 14 th day. According to the results it is concluded that the essential oil of L. angustifolia, can be used either directly or incorporated into the cosmetics without the necessity for any other extra preservative against the above mentioned microrganisms.