Essential oil (EO) of Thymus eigii (Lamiaceae) was hydrodistillated and characterized using with GC/MS. Forty-three constituents were determined accounting 100 % of the EO. The predominant constituents were thymol (24.77 %), carvacrol (14.00 %), p-cymene (10.91 %), -terpinene (6.53 %) and borneol (6.48 %). EO showed different levels of antimicrobial activities on test microorganisms. C. albicans, C. parapsilosis and S. aureus ATCC 29213 had the MIC/MFC/MBC values with 0.07/0.18 mg/ml, 0.18/0.36 mg/ml and 0.36/1.22 mg/ml respectively. EO of T. eigii exhibited pronounced herbicidal activities by inhibiting the germination and the growth of the seedlings of all plant species.