This study evaluates the protective effects of sinapic acid (SA), a polyphenolic compound with diverse biological activities, against ethanol-induced gastric ulcers in rats. A gastric ulcer model was established using ethanol (ETH), and the experimental groups received either omeprazole (OMEP, 20 mg/kg) or SA at doses of 20 mg/kg and 40 mg/kg via oral gavage for 14 days. Biochemical markers, including total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), malondialdehyde (MDA), and myeloperoxidase (MPO) activity, were assessed alongside proinflammatory cytokines (tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and IL-6) using ELISA. Histopathological and immunohistochemical analyses were conducted to evaluate tissue integrity and apoptosis. Statistical analysis was performed using one-way ANOVA, followed by Tukey's HSD test for post hoc comparisons. For non-parametric data, the Kruskal-Wallis test and Mann-Whitney U test were used. A p-value < 0.05 was considered statistically significant. Results revealed that SA significantly enhanced antioxidant defenses, as evidenced by elevated TAS levels and reductions in TOS, OSI, MPO activity, and MDA levels (p < 0.05). Additionally, SA treatment mitigated inflammation and apoptosis by decreasing TNF-α, IL-1β, IL-6, and Bax expression (p < 0.05). These effects were comparable to those observed with OMEP, a widely used clinical agent. Notably, the findings underscore SA's potential as a novel therapeutic agent for managing ethanol-induced gastric ulcers. By targeting oxidative stress and inflammatory pathways, SA could complement or serve as an alternative to current treatment strategies. Future research should focus on exploring SA's molecular mechanisms, dose optimization, and long-term efficacy in clinical settings, paving the way for its integration into therapeutic regimens for gastric mucosal injuries.