Background: Clostridium perfringence is one of the most important pathogens in animals and cause a lot of death in sheeps and goats every year. In human C. perfringence cause food intoxication and gastroentritis.

Objective: This study was conducted to determine the antimicrobial effects of essential oils of Thymus daenensis, Hypericum Scabrum , pimpinella anisum on clostridium perfringens in the laboratory culture media.

Methods: After extracting the essential oils by Steam Distilation method ، antimicrobial activity were examined by two methods. At first in the plate method after culturing bacteria on the plate containing Nutrient Agar, 5 mm diameter hole was made by the sterile pastuer pipte and 0.1 ml of each essential oils was added to each whole separetely. In the second step tube dilation method containing Tyoglycolate broth was used to determining the MIC and MBC of the essential oils.

Results: The results showed that the pimpinella anisum oils had not any effect on growth of C. perfringence, but the mean value of inhibitory zones for thymus daenensis and Hypericum Scabrum oils were 8.1 ± 0.2 and 6.03 ± 0.15 respectevely. The MIC for thymus daenensis and Hypericum Scabrum oils were 5% and 15% respectively. The results showed that the MBC of Thymus daenensis and Hypericum Scabrum oils for C. perfringence were 20% and 40% respectively.