The chemical variability of the essential oils of Artemisia herba-alba Asso aerial parts, collected at Algeria was evaluated. A. herba-alba populations were collected in four regions, Benifouda; Bougaa; Boussaada and Boutaleb, at two different periods, July (flowering phase), and October and November (vegetative phase). The essential oils were isolated by hydrodistillation and analyzed by Gas Chromatography (GC) and Gas Chromatography-Mass Spectrometry (GC-MS). The essential oils yield ranged between 0.2% and 0.9% (v/d.w.). Fifty components were identified in A. herba-alba oils, oxygen-containing monoterpenes being dominant in all cases (72–80%). Camphor (17–33%), a-thujone (7–28%) and chrysanthenone (4–19%) were the major oil components. Despite the similarity in main components, three types of oils could be defined, (a) a-thujone : camphor (23–28: 17–28%), (b) camphor : chrysanthenone (33:12%) and (c) a-thujone : camphor : chrysanthenone (24:19:19%). The comparison between the present data and an updated survey of the existing literature reinforces the major variability of A. herba-alba essential oils and stresses the importance of obtaining a defined chemical type crop production avoiding the wild harvest.