Achillea biebersteinii (A. biebersteinii), one of the Achillea species, has been proven to have positive effects in terms of pharmaceuticals thanks to the components it contains. Our study was designed to investigate the quenching activity of A. biebersteinii on total phenolic component, total flavonoid component and DPPH radical. The total flavonoid component amounts of the ethanol and water extract of A. biebersteinii plant were calculated to be equivalent to quercetin, and the total phenol component amounts to gallic acid. The DPPH radical quenching activity of the ethanol and water extract of the A. biebersteinii plant was investigated by modifying the Teixeira method. The copper II ion reduction method (CUPRAC) is inspired by the Apak method. We can say that the water and alcohol extract of A. biebersteinii gave good results compared to BHA and BHT, which have good quenching activity on DPPH radical. It was observed that A. biebersteinii was rich in flavonoids and phenolics. As a result of Cuprac analysis, it was stated that the effect of the aqueous extract was significant compared to the positive controls. The A. biebersteinii plant is thought to be effective in the treatment of many diseases, especially cancer, due to its powerful antioxidant and radical quenching activity.