Background: ST-segment elevation myocardial infarction (STEMI) is a form of acute coronary syndrome with high mortality rate. Management of STEMI should be performed as soon as possible to prevent further damage. With the emergence of coronavirus disease 2019 (COVID-19), it may face obstacles. To overcome those problems, some changes in policy focusing on fibrinolytic therapy in STEMI patients have been applied. This study aimed to identify the effects of COVID-19 in management of STEMI patients in Indonesia. Methods: This retrospective study was conducted in Dr. Cipto Mangunkusumo Hospital (CMH), the national referral center in Indonesia. We compared data between 2018 to 2019 and 2020 to 2021 as before and during COVID-19 pandemic period, respectively. We analyzed the effects of COVID-19 on STEMI patients' visits to hospital i.e., monthly hospital admission and symptoms-to-hospital, management of STEMI i.e., the strategies and time of reperfusion, and clinical outcomes of STEMI patients i.e., major adverse coronary event and mortality. Results: There was a significant statistically reduced mean of monthly hospital admissions from 11 to 7 (p = 0.002) and prolonged duration of symptoms-to-hospital during COVID-19 from 8 to 12 hours (p = 0.005). There was also a decrease in primary percutaneous coronary intervention (PPCI) procedures during COVID-19 (65.2% vs. 27.8%, p