Salvia species is among the most important plants of the Lamiaceae family; it is an aromatic plant rich in essential oils used in food, cosmetics, perfumes and pharmaceuticals. This work aims to examine the sage essential oil from Mascara region (North West of Algeria). The essential oil was isolated from aerial part of Salvia officinalis by hydrodistillation and volatile compound were analyzed using gas chromatography coupled with the GCMS spectrometry. The results showed that sage provides a higher yield of essential oil. The chemical composition of Salvia officinalis essential oils varies widely, and three major chemotypes have been identified α- Thujone (15,49%), Camphor (15,21%) and Eucalyptol (11,26%). Other important compound were Viridiflorol (4,55%), β-Thujone (3,56%), 1-Naphthalenepropanol, .alpha.-ethenyldecahy (3%), Camphene (2,76%), β- Pinene (2,21%), Borneol (1,72%) followed by α- Pinene (1,29%) and α- Terpinolene (1,18%).