Mesenchymal stem cells (MSCs) have captured the attention of researchers today due to their multipotent differentiation capacity. Also, they have been successfully applied clinically, in the treatment of various diseases of the heart and musculoskeletal systems, with encouraging results. Their supportive role in haematopoiesis and their anti-inflammatory and immunomodulatory properties have enhanced their contribution towards the improvement of engraftment and the treatment of graft-versus-host disease in patients receiving haematopoietic stem cell transplantation. However, there is a growing body of research that supports the involvement of MSCs in leukaemogenesis with several genetic and functional abnormalities having been detected in the MSCs of leukaemia patients. MSCs also exert leukaemia-enhancing effects and induce chemotherapy resistance in leukaemia cells. This paper addresses the key issues in the therapeutic value as well as the harmful effects of the MSCs in leukaemia with a sharp focus on the recent updates in the published literature.