Wine is one of the most consumed beverages over the world. Wine is an alcoholic beverage that contains various polyphenols extracted from grapes during the processes of vinification. The polyphenolic compounds, such as flavonoids, anthocyanins and tannins are considered to have antioxidant activity, protecting the body cells against oxidation. These compounds are present in large quantities in wine, especially in red wines, which may explain so-called French paradox. Moreover, polyphenolic compounds are responsible for the quality of wines, influencing their astringency, bitterness and colour. The viticulture practices, different enological techniques, the varieties and the harvesting year of grapes and the wineries influence the polyphenolic composition of wines. Different studies have been carried out in order to analyze the different compounds from wines, especially polyphenolic compounds. Romania is the fifth large wine-producing country in Europe, after Spain, France, Italy and Portugal, with an area of about 200,000 ha cultivated with grapevines. The annual production of wine is about 5 million hectolitres and the consumption per person is approximately 27 L. Wine quality assurance and monitoring are of major interest because the accession of Romania to the EU was accompanied with compliance with rules related to authentication of grape and wine varieties. This is due to numerous counterfeit wines that still exist on markets in Eastern Europe. Thus, two of the principal analytical goals are the development of methods for evaluation of authenticity of the end product and detection of possible adulterations.