The objective of this work is to identify the bioactive molecules in the essential oil of the dried leaves of Rosemary from two cities in the Eastern region of Morocco: Taourirt and Jerrada. These essential oils have already been extracted by the steam distillation method in the cooperative. the chemical composition have been determined by gas chromatography coupled with mass spectrometry (GC/MS), in which cineole 41.77%, alpha-Pinene 10.75% and Camphor 9.32% represent the majority compounds for essential oil of Rosemary from Taourirt and cineole 51.68%, alpha-Pinene 11.91 % and Camphor 10.29 % predominate in that of Jerada rosemary. Antioxidant activity in vitro was assessed in three different ways: the DPPH test, the β-carotene bleaching technique, and the reduction power measurement. The DFT analysis of the different compounds and the Docking study were also investigated in objective to study the molecular reactivity of the majority compounds, also study their affinity to various cyclodextrin as prospective encapsulation systems.