Abstract:L-ascorbic acid (AA) can not only inhibit oxidation and browning of food but also cause degradation and oxidation of food to produce brown pigments. Therefore, it is very important to completely understand the degradation mechanism of AA in order to maintain the stability of AA in food. In this paper, the self-degradation mechanism of AA under different conditions (oxygen content, temperature, pH, and substrate concentration) and the degradation process via the Maillard reaction involving the oxidation products of AA were reviewed in detail. In addition, the beneficial and adverse effects of dehydroascorbic acid (DHAA), a degradation product of AA, on food properties were summarized. DHAA can be crosslinked with sulfhydryl groups of gluten to improve the properties of gluten. In contrast, DHAA causes the degradation of phenols and reduces the antioxidant capacity of food. Moreover, DHAA can form glycosylation end products with proteins and produce substances harmful to the human body. This review aims to provide a more comprehensive research perspective for the degradation of AA during food processing.