The aim of our work is the characterization of the chemical composition and evaluation of the antibacterial activity of the essential oil and methanol extract of Thymus satureioides growing wild in the eastern High Atlas of Morocco. The extraction of the essential oil of the aerial parts of the plant was carried out by steam distillation. The yield of essential oil is 2,74%. The methanolic extract is obtained by maceration with methanol at 80%, and the yield is of the order of 11,66%.The results of the chromatographic analysis GC-MS of the Thymus satureioides Essential oils have allowed to identify around 35 constituents. The major ones are Carvacrol (30,47%); Borneol (18,15 %); β -cymene (12,69 %); Camphene (6,19%); α-pinene (3,77%) and γ-terpinene (3,66%). The antibacterial activity of the essential oils and that of the methanolic extract of Thymus satureioides has been studied with the help of the amatograms method through five pathogene bacterial strains for people: Klebsiellapneumoniae, Staphylococcus aureus, Pseudomonas aeruginosa, wild Escherichia coli and acquired Escherichia coli penicillinase. The obtained results showed that the essential oils of Thymus satureioides represent excellent activities vis-à-visall tested strains with MICs ranging from 0, 68mg / ml and 21,73mg/ml.Thisstrong antibacterial activity is attributed to the major constituents, especially ʽcarvacrol’ known by these important antibacterial properties.However,this oil is more active than Imipenem and Amoxicillin used as a reference antibiotics. As for the methanol extract of this species, it represents a low activity vis-à-vis the same strains. The strong antibacterial activity of this species justifies its use in traditional medicine for the treatment of many infectious diseases.