Despite aggressive treatment, the mortality rate of cardiogenic shock with acute myocardial infarction (AMI) is high. We performed extracorporeal membrane oxygenation (ECMO) prior to coronary reperfusion, and evaluated the early clinical results and risk factors. Materials and Methods: From May 2006 to November 2009, we reviewed the medical records of 20 patients in cardiogenic shock with AMI (mean age $67.7{pm}11.7$ yrs, M : F 14 : 6). After initially performing ECMO using the CAPIOX emergency bypass system ($EBS^{(R)}$Terumo, Tokyo, Japan), patients underwent coronary reperfusion (coronary artery bypass grafting, 13; percutaneous coronary intervention, 7). Results: All patients were in a cardiogenic shock state, cardiopulmonary resuscitations (CPR) were performed for fourteen patients (mean CPR time $20.8{pm}26.0$ min). The mean time from vascular access to the initiation of ECMO was $17.2{pm}9.4$ min and mean support time was $3.8{pm}4.0$ days. Fourteen patients were able to be weaned from ECMO and ten patients were discharged (mean admission duration $50.1{pm}31.6$ days). Patients survived on average $476.6{pm}374.6$ days of follow-up. Longer CPR and support time, increased cardiac enzyme, lower ejection fraction, lower albumin, and major complications were the risk factors of mortality (p<0.05). Conclusion: The early application of ECMO prior to coronary reperfusion and control of risk factors allowed for good clinical results in cardiogenic shock with AMI.