The delayed healing of diabetic wounds (DBW) will not only afflict patients, but also lead to amputation and even death in serious cases, which will create many negative effects on society and the country. Mesenchymal stromal cells (MSCs) have attracted extensive attention for their applications in chronic wound healing due to their excellent cytokine secretion ability and regulation of inflammation. Mesenchymal stromal cells can be used alone or wrapped with carrier/matrix and applied to enhance healing in the wound area. In this review, the etiology of the slow healing of DBW and the mechanism by which MSCs promote the healing of DBW were explored. In addition, we summarised the current research progress on the use of stromal cell-loaded biomaterials for wound healing in diabetic animal models. At the end of the article, we pointed out the challenges and improvement strategies for stromal cell therapy applied to DBW in future clinical practice.