Fennel is a plant known for its very specific smell, used in cough syrups and in food industry. Fennel essential oil is extracted primarily through steam distillation from seeds of bitter fennel Foeniculi amari fructus – Foeniculum vulgare Mill., Apiaceae. Typical qualities of the oil are anethol, phencone and estragole. Oil is an effective smell corrector, thus it is an active ingredient of natural cosmetics. It aids in treating colic, tympanites, and it has secretory properties that work effectively on respiratory tract. It helps to treat symptoms of bronchitis and asthma. Fennel essential oil has bacteriostatic properties, thus it is an active preservative of various preparations. Oral application without supervision of the qualified person is not recommended. It is not generally recommended during pregnancy or while breastfeeding, and for children under the age of 12.