Cellular replacement therapy for diabetes mellitus (DM) has received much attention. In this study, we investigated the effect of transplantation of autologous bone marrow‑derived mesenchymal stem cells (ABMSCs) in streptozotocin (STZ)‑induced diabetic miniature pigs. Miniature pig BMSCs were cultured, labeled with superparamagnetic iron oxide (SPIO) and transplanted into the pancreas of diabetic miniature pigs through targeted intervention. Blood glucose levels, intravenous and oral glucose tolerance test (OGTT), serum insulin, C‑peptide and islets histology were analyzed. These transplanted cells were then identified by magnetic resonance imaging (MRI). The results showed that transplantation of ABMSCs reversed STZ‑induced diabetes in miniature pigs. Blood glucose levels, intravenous, OGTT, serum insulin and C‑peptide were significantly recovered in the diabetic minipigs with the autologous BMSC (DMAB) transplantation group. In addition, the number of islets was significantly increased in this group compared to the diabetic minipig control (DMC) group with conventional therapy. These data suggested the implantation of autologous BMSCs for type 1 diabetes treatment can partially restore the function of islet β cells and maintain blood glucose homeostasis. Transplanted autologous BMSCs may improve islet repairing by differentiating for new islets and change pancreatic microcirculation and be identified in a real‑time manner using MRI in vivo.