Two-year-old roots of the dandelion (Taraxacum officinale), whose collection was carried out in six stages, from May till October, were used in laboratory experiments. The presence of four phenolic acids: caffeic acid cichoric acid, chlorogenic acid and p-hydroxybenzoic acid was identified and confirmed by the HPLC method. The changes in content of particular phenolic acids in the roots collected at various stages were also identified. The roots, the collection of which was carried out at blossoming stage indicated the highest content of chlorogenic and cichoric acid.