Extensive reviews of research are available on the use of ascorbic acid, and its consequent degradation pathways, inphysiological conditions or food matrices. However, very little information can be found for wine-related systems. Thisreview highlights the relevant chemistry and reactivity of ascorbic acid with a focus on its behavior and potential behaviorin a wine environment. The review describes the use of ascorbic acid as a complementary antioxidant preservative to sulfur dioxide along with the metal-catalyzed and radical-dependent manner by which it achieves this role. The relevantdegradation products of ascorbic acid in aerobic and anaerobic conditions are presented as well as the interaction of thesedegradation products with sulfur dioxide and other wine-relevant sulfur compounds. Limitations in existing knowledge,especially regarding the crossover between the antioxidant and pro-oxidant roles of ascorbic acid, are identified.