Background: In recent years, various preclinical animal studies showed the potential of stem cell therapy to regenerate myocardium and improve cardiac function. Adipose tissue has been identified as a source of pluripotent cells that have the capacity to differentiate into cardiac myocytes, endothelial cells, similar to bone marrow cells. In present study, we have investigated the effect of ADSCs (adipose tissue derived stromal cells) therapy on cardiac contractility and remodeling in C57BL/6 mouse model of AMI. Materials and Methods: Total 30 adult male C58BL/6 mice (12 weeks of age, 28~30g body weight) were used for this study. Animals were randomized into two groups: MI+media (n=15) and MI+ADSCs (n=15). AMI was produced by coronary artery (LAD) ligation. Following AMI induction, intramyocardial injection of 1��106 ADSCs was compared to the injection of media alone. Animals were analyzed using Echocardiography at 2 weeks after transplantation, and then sacrificed for histologic assessment. Results: The FS and LVEF improved in ADSCs transplant group at 2 weeks to compare with control group (p<0.05). LVEDD in ADSCs transplant group compared to control group showed a little decrease from 4.65짹0.63mm (control) to 4.14짹0.53mm (ADSCs); but there was no statistical difference (p=0.072), whereas LVESD decreased significantly in cell transplantation group compared to control group (p<0.05). We found a significant difference between ADSCs transplant group and control group (media) in injury size, infarct area, wall thickness or scar formation at 2 weeks after AMI. In our study, ADSCs have been showed to migrate into the injured sites and to integrate into the scar areas. In addition, some of transplanted ADSCs were able to express endothelial marker. Conclusion: The cardiac function and ventricular remodeling improved greater in ADSCs transplant group than that in control group. This suggests that ADSCs could be a good candidate as a novel source of cell therapy in cardiovascular disease