Nowadays, medicinal plants used in folk medicine are being increasingly studied and used on pharmaceutical, food and nutraceutical fields. Yarrow (Achillea millefolium L.) is widely used in both folk and official medicine. Therefore, in the present paper different extracts of yarrow - inﬂorescences and upper leaves were investigated for their total polyphenolic content and antioxidant activity using several reliable assays, namely DPPH-, ABTS-, FRAP- and CUPRAC assays. The phytochemical profile of the extracts was assessed by RP-HPLC methods as well in order to evaluate the inﬂuence of the single constituents. The total polyphenolic content of the extracts was established to be in range 2.74 ± 0.01 and 7.92 ± 0.09 mg GAE/g dw. Among the four applied techniques for extraction the decoction seems to be still the most effective ones. However, the results revealed that the extracts of the Achillea millefolium could be used as easily accessible source of natural antioxidants, but also as a possible food supplement or in pharmaceutical industry.