Diabetic cardiomyopathy (DCM) is considered one of the main diabetic complications, contributing to specific forms of heart failure independent from hypertension or ischemia. There are increased research efforts to further explore a new potential therapeutic strategy for preventing or reversing DCM progression. The present research aimed to explore which type of stem cell-based therapies could serve as an effective tool for the treatment of DCM in type 1 diabetic rats. Four groups of male Wistar rats have been used in this study including the control group, a diabetic-untreated group, and two diabetic rat groups treated with either mesenchymal stem cells (MSCs) derived from adipose tissue (AD-MSCs) or bone marrow (BM-MSCs). Interestingly, serum levels of heart dysfunction markers (LDH and CK-MB) in the diabetic rats were found to be declined to near-normal levels following injection with either of the two MSCs types. Also, BM-MSCs or AD-MSCs (1×10⁶ cell/rat)-treated diabetic rats exhibited significant decreases in the cardiac xanthine oxidase activity, reactive oxygen species, and malondialdehyde level, accompanied with marked elevations in various antioxidants, compared with the diabetic untreated group.The results also clearly point out the excellence of AD-MSCs injection as a potential agent in alleviating the DCM over BM-MSCs injection.