The aim of this study is to investigate the potent antioxidant capacities of Taraxacum officinale leaf extract. Asteraceae family, the genus Taraxacum is widespread in the Mediterranean countries, with approximately 2000 species worldwide. Taraxacum officinale, a species that stands out in phytotherapy, is a perennial plant with yellow flowers commonly found in the warm regions of Asia and Europe. Initially used in folk medicine for liver diseases, it has been observed over time that it is also used for various diseases such as dyspepsia and urinary system disorders. T. officinale contains numerous phenolic compounds contributing to antioxidant, anti-inflammatory, and antimicrobial activities. This research aimed to evaluate the antioxidant capacities of aqueous and ethanol-water extracts prepared from T. officinale leaves. Antioxidant capacities were assessed using spectrophotometric methods in DPPH, FRAP, and CuPRAC forms. The results showed that the DPPH, FRAP, and CuPRAC values were higher in the 50% ethanol extract of T. officinale leaves: 137.1 mg Trolox/g (DPPH method), 132.7 mg Trolox/g (FRAP method), and 409.9 mg Trolox/g (CuPRAC method). In conclusion, Taraxacum officinale leaves clearly demonstrate to be a rich source of polyphenols with high antioxidant properties. It has no seious side effect or toxicity. Considering its lack of serious side effects and toxicity, when formulated into herbal medicine, it could be effective in the treatment of various diseases, especially common liver and bile diseases, based on its biological activity studies.