Management of patients with multiple myeloma having several coexisting comorbid medical conditions is a real challenge as complications related to the primary disease, its treatment and other comorbidities are prone to occur. In such complicated cases, an individualized therapy has to be adopted. A 45 year old male, with pre-existing end-stage renal disease, diabetes mellitus and hypertension, was diagnosed to have multiple myeloma in October 2012 at King Fahad Specialist Hospital in Dammam, Saudi Arabia. The diagnosis of diabetes was made one year prior to the diagnosis of his myeloma and he was receiving 40 to 50 units of insulin per day to control his diabetes. After receiving 4 cycles of bortezomib, lenalidomide and dexamethasone, his myeloma was controlled then in March 2013, an autologous hematopoietic stem cell transplantation was performed. One month following his autograft, his insulin requirements started to decrease gradually and 4 months post-transplantation his diabetes became insulin independent. For more than 4 years after his stem cell transplantation, both his diabetes and multiple myeloma are still under control. To our knowledge, this is the first world report of diabetes mellitus cured by stem cell therapy performed to control a hematologic malignancy.