Artemisia dracunculus (tarragon) has been used orally as an antiepileptic remedy in Iranian folkloric medicine. In the current study, the morphological variation and the essential oil composition from the aerial parts of the plant were evaluated. The results indicated significant differences among genotypes for morphological traits and clustering based on these traits classified the genotypes into two clusters. The essential oil content ranged from 1.42 to 2.53 v/w. Analysis of the essential oil revealed the presence of methyl chavicol (68.21–81.11%), limonene (7.18–16.73%), terpinolene (0.01–7.68%), (Z)-β-ocimene (0.89–4.99%), (E)-β-ocimene (0.81–4.52%), methyl eugenol (0.90–2.67%) and α-pinene (0.43–1.91%) as the main components. Variables related to leaf were found to be associated with all phytochemical compositions, indicating a main role of leaf on production of these compounds. These data collectively demonstrated large phenotypic and chemical diversity among the selected genotypes which can be considered as a valuable gene pool for breeding programs.