Phenolic compounds in wines, especially in red wines, possess strong antioxidant activity in vitro. Phenolic compounds, obtained in red wine, are natural constituents of grapes and wines. They have the largest effect in decreasing atherosclerosis by both hypolipemic and antioxidant mechanisms. Thus, phenolics show a positive effect on human health and they may cause an increase of antioxidant activity of blood plasma. In this book, the effect of total phenolics [TP], total anthocyanins [TA] on the antioxidant activity [AA] is discussed. Furthermore, the applications of the different analytical methods that have been developed so far for the analysis of natural antioxidants in red wine are discussed, such as high-performance liquid chromotography (HPLC), gas chromatography (GC), and capillary electrophoresis (CE). Also, the agents influencing the phenolic profiles of red wine are overviewed.