Summary While qualitative studies have identified chlorogenic acids in antioxidant extracts, particularly ethyl acetate‐derived extracts, of Taraxacum officinale , quantitative analysis of these phenolic compounds remains largely unreported for this species. In this study, bioactivity‐guided fractionation of an antioxidant crude ethyl acetate extract ( DPPH = 295.481 ± 0.955 mg TE g −1 extract) from T. officinale root resulted in a number of reverse‐phase fractions that demonstrated high antioxidant activity ( DPPH = 1058.733–1312.136 mg TE g −1 extract), stronger than that of the synthetic antioxidant Trolox ® . UPLC ‐ MS / MS screening of these fractions for the presence of selected mono‐ and di‐caffeoylquinic acids revealed large quantities of 1,5‐dicaffeoylquinic acid present in several fractions (853.052–907.324 μg mg −1 ), respectively. Due to the antioxidant potency and high levels of 1,5‐dicaffeoylquinic acid observed in these fractions, it was concluded that specifically this chlorogenic acid derivative is a major contributor to the antioxidant efficacy of dandelion root.