Abstract: Background: Arising medications and their complications in recent years, and as a reason using alternative folk medications will be a solution for many diseases. The rule of medicinal plants is to strengthen the defense mechanism of the body with natural products such as polyphenols, which is a way to fight diseases and their complications. Pimpinella anisum proved to be able to treat many diseases, but its phenolic constituents are not fully identified, also its antioxidant ability needs more studies. Methodology: Pimpinella anisum Libyan endemic plant was extracted by acetone through socking; the solvent was then evaporated and the extract was analyzed for antioxidants using DPPH and phenolic compounds using HPLC. The Results: antioxidant activity was proved for acetone extract with IC50 of 7.83 ug/ml, and 15 polyphenolic compounds were identified by HPLC with different concentrations. Conclusion: We suggest considering this study as a seek for future studies on Pimpinella anisum.