: Diabetes mellitus (DM) is a chronic metabolic disease that characterized by persistent hyperglycemia and glucosuria. Type 1 diabetes is an autoimmune disease, mostly affects dogs and is manifested clinically by polyuria, polydipsia, polyphagia, and weight loss.The presence of characteristic clinical symptoms and glycemic profile tests, such as blood glucose concentration (BGC), insulin, c-peptide level, fructosamine (SFA), and hyperglycated haemoglobin concentration (HBA1c), are used to diagnose diabetes mellitus. One of the common therapeutic options accessible nowadays is insulin therapy. However, the majority of T1DM patients receiving insulin therapy are unable to keep their blood glucose levels within the normal range, and there is a risk of developing dangerous hypoglycemia. This led to look for other strategies for controlling blood glucose level. It is evident that the current standard therapy for diabetics fails to mimic the insulin secretion of healthy beta cells. As a result, exogenous insulin is more life-saving than curative. Therefore the two main strategies for treating type 1 diabetes mellitus reestablishing the insulin secretion mechanism and creating new islet β-cells. This new trial involves mesenchymal stem cells (MSCs), as they possess regenerative and immunomodulatory properties and can control immunological dysregulation that leads to beta cell death. Therefore, insulin-dependent diabetes mellitus in dogs may be treated with stem cell transplantation (IDDM). Though MSCs have been isolated from different sources, all show excellent improvement in the clinical cases.