SARS-Cov-2 has been suggested to promote thrombotic complications and higher mortality. The aim of the present study was to evaluate the impact of SARS-CoV-2 positivity on in-hospital outcome and 30-day mortality in ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PCI) enrolled in the International Survey on Acute Coronary Syndromes ST-segment elevation Myocardial Infarction (ISACS-STEMI COVID-19 registry. The 109 SARS-CoV-2 positive patients were compared with 2005 SARS-CoV-2 negative patients. Positive patients were older (P = .002), less often active smokers (P = .002), and hypercholesterolemic (P = .006), they presented more often later than 12 h (P = .037), more often to the hub and were more often in cardiogenic shock (P = .02), or requiring rescue percutaneous coronary intervention after failed thrombolysis (P < .0001). Lower postprocedural Thrombolysis in Myocardial Infarction 3 flow (P = .029) and more thrombectomy (P = .046) were observed. SARS-CoV-2 was associated with a significantly higher in-hospital mortality (25.7 vs 7%, adjusted Odds Ratio (OR) [95% Confidence Interval] = 3.2 [1.71-5.99], P < .001) in-hospital definite in-stent thrombosis (6.4 vs 1.1%, adjusted Odds Ratio [95% CI] = 6.26 [2.41-16.25], P < .001) and 30-day mortality (34.4 vs 8.5%, adjusted Hazard Ratio [95% CI] = 2.16 [1.45-3.23], P < .001), confirming that SARS-CoV-2 positivity is associated with impaired reperfusion, with negative prognostic consequences.