Thirty-one red wines of "Protected Geographical Indication", including most of the wine cultivars grown in Sicily, were assayed for their phenolic content. Individual phenolic compounds were identified and quantified by HPLC with a photo-diode array (PDA) coupled on-line with a MS system. The total phenolic content was evaluated by the Folin-Ciocalteau method and the antioxidant capacity was measured by the DMPD (N,N-dimethyl-p-phenylendiamine) method. The results provide new insight into the polyphenolic composition of commercial Sicilian wines, and highlight some interesting points about the different wine typologies. In particular, the Merlot wines produced in Sicily, similar to those produced by other allochthonous grapes, generally have a higher polyphenolic content. Based on the data given, Merlot wines appear to be an important source of dietary polyphenolic antioxidants. It may be supposed that wines produced from this grape typology in Sicily are endowed with properties that have potential health benefits.