Type 1 diabetes represents a serious disease which is caused by autoimmune destruction of insulin-producing B cells in the pancreas. Administration of exogenous insulin cannot replace sensitive and gentle regulation of blood glucose levels that is established by B cells in healthy individuals. Pancreas or islet transplantation is limited by a shortage of donor pancreas and by complications associated with transplantations. For those reasons, new approaches of treatment are being searched, the using of mesenchymal stem cells (MSCs) envisions a promising tool for cell-based therapy of type 1 diabetes. MSCs have a significant impact on the regulation of the immune system, are a potent source of various cytokines and growth factors and manifest multilineage differentiation abilities. In context of type 1 diabetes, MSCs can transdifferentiate into insulin-producing cells, support the regeneration of residual B cells by production of trophic and growth factors or participate in the suppression of the autoimmune reaction against B cells. This review is focused on perspectives and mechanisms of MSC-based therapy and its limitations. Key words: autoimmune reaction - differentiation - mesenchymal stem cells - type 1 diabetes.