Due to the increasing drug resistance microorganisms and and tend to use medicinal plants in the present study, biochemical composition and antifungal effects of Thymus Kotschyanus essential oil against Candida albicans,krusei and glabrata have been evaluated. in this study, the chemical composition and antifungal activity essential oil by the Gas chromatography/ mass spectrophotometer (GC/MS) and micro dilution method was determined respectively. The collected data was analyzed by the Minitab 16 software using ANOVA. The chemical analysis of the essential oil by Gas chromatography/ mass spectrophotometer (GC/MS) revealed the presence of 45 substances, mainly including carvacrol (52.4%), Gamatrpynen (12.1%) and thymol (10.4). MIC and MBC of the essential oil determined in the range of 0.25 to 0.5 and 0.5 to 1 μg/ ml, respectively. The results of this study indicate that essential oil Thymus Kotschyanus have a high antibacterial activity. Due to drug resistance and side effects of antifungal drugs are chemical can  more studies of thyme essential oil as a natural anti-fungal drug use.