This study investigated the effect of 8 weeks of high-intensity interval training (HIIT) on oxidative stress, inflammation, and apoptosis in rats with type 2 diabetes (T2D), focusing on the role of the Humanin (HN). In this study, 28 male Wistar rats were assigned to one of four groups: healthy control (CO), diabetes control (T2D), exercise (EX), and diabetes + exercise (T2D + EX). After diabetes induction (2-month high-fat diet and injection of 35 mg/kg streptozotocin), the animals in the EX and T2D + EX groups underwent an 8-week HIIT protocol (4-10, interval of 80%-100% of maximum speed). HOMA-IR, fasting blood glucose, and HN levels were measured in the serum. The expression of HN, Bax, Bcl-2, CAT, GPx, MDA, TNFα, and IL-10 was measured in the soleus muscle. Our results showed that the serum level of HN and the muscle levels of IL-10, SOD, CAT, and Bax were higher in the T2D + EX group than in the T2D group. However, the HOMA-IR index and the muscle levels of MDA, TNFα, and Bcl-2 were lower in the T2D + EX group than in the T2D group. Muscle levels of HN and GPx showed no significant difference between the T2D + EX and T2D groups. The result of Pearson analysis showed a significant correlation between HN and MDA, SOD, Bax and Bcl-2. This study provides evidence that there is a correlation between serum Humanin levels and HIIT. HIIT benefits T2D rats by reducing inflammation and oxidative stress. Given Humanin's established involvement in inflammation and oxidative stress, it is possible that the benefits of HIIT on T2D rats are mediated by humanin.