The present study describes for the first time the optimization of the extraction by hudrodistillation and chemical composition of the essential oil (EO) of Ballota hirsuta aerial parts using Gas chromatography (GC/FID) and GC-mass spectrometry (GC/MS) analysis. Single-factor experiments and response surface methodology (RSM) based on a central composite design (CCD) were used to optimize the EO extraction parameters including drying period (0–21 days), extraction time (60–240 min) and water/plant ratio (5–20 ml/g). The optimum conditions for obtaining the best yield (0.91%) are a drying period of 7 days, an extraction time of 120 min and a water/plant ratio of 10 ml/g. Under these optimum condition, GC/FID and GC/MS enabled the identification of forty-three volatile components representing 82.3% of the total of EO. Germacrene-D (16%), Z-Phytol (7.7%), α- Cadinol (7.3%) and Carvacrol (6.7%) were the main constituents of this EO.