Culinary herbs and medicinal plants could be used as natural food ingredients to replace synthetic antioxidants. Two natural antioxidant preparations, namely Rosmol (liquid) and Rosmol-P (powder) were produced by extraction from a mixture of medicinal plants belonging to the Lamiaceaefamily, such as rosemary (Rosmarinus officinalis L.),self heal(Prunella vulgaris L.)hyssop(Hyssoppus officinalis L.)and lemon balm (Melissa officinalis L.). The main active compound of the extract is supposed to be a phenolic (caffeic) acid derivative. The total polyphenol content of the preparations is very high, 8.72 g l-1for Rosmol and 93.7 g kg-1for Rosmol-P. The products acted as primary and secondary antioxidants, chelating transitional metal ions and inhibiting the autoxidation of linoleic acid. Rosmol and Rosmol-P scavenged free radicals formed during Fenton type reaction measured by chemiluminometry, and also exhibited strong antioxidant property in Randox TAS measurement. The antioxidant activity of the products was unchanged after six months of storage. According to the in vitro studies, the products are suitable to use as antioxidant ingredients instead of synthetic ones in lipid containing food products.