Myocardial infarction (MI) is a serious complication of coronary artery disease. This condition is common worldwide and has a profound impact on patients' lives and quality of life. Despite significant advances in the treatment of heart disease in modern medicine, the efficient treatment of MI still faces a number of challenges. Problems such as scar formation and loss of myocardial function after a heart attack still limit patients' recovery. Therefore, the search for a new therapeutic tool that can promote repair and regeneration of myocardial tissue has become crucial. In this context, mesenchymal stromal cells (MSCs) have attracted much attention as a potential therapeutic tool. MSCs are a class of adult stem cells with multidirectional differentiation potential, derived from bone marrow, fat, placenta and other tissues, and possessing properties such as self-renewal and immunomodulation. The application of MSCs may provide a new direction for the treatment of MI. These stem cells have the potential to differentiate into cardiomyocytes and vascular endothelial cells in damaged tissue and to repair and protect myocardial tissue through anti-inflammatory, anti-fibrotic and pro-neovascularization mechanisms. However, the clinical results of MSCs transplantation for the treatment of MI are less satisfactory due to the limitations of the native function of MSCs. Genetic modification has overcome problems such as the low survival rate of transplanted MSCs in vivo and enhanced their functions of promoting neovascularization and differentiation into cardiomyocytes, paving the way for them to become an effective tool for repair therapy after MI. In previous studies, MSCs have shown some therapeutic potential in experimental animals and preliminary clinical trials. This review aims to provide readers with a comprehensive and in-depth understanding to promote the wider application of engineering MSCs in the field of MI therapy, offering new hope for recovery and improved survival of cardiac patients.