 The COVID-19 pandemic has had a major impact on the emergency medical care system, resulting in worse outcomes for patients suffering from out-of-hospital cardiac arrest, OHCA. Compared to before the pandemic, survival and favorable neurological outcomes have been significantly lower, while the use of an automated external defibrillator, AED, response time of emergency medical services, EMS, and the incidence of cardiac arrest at home have all increased. Additionally, the use of mechanical CPR, bystander CPR, and unwitnessed cardiac arrest have also increased. However, no significant regional differences in survival rates were observed between the pre-pandemic and post-pandemic periods. This article was authored by J-Hwon Kim, Chi Won-an, Yongkyung Park, and others.