The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causing the coronavirus disease 2019 (COVID-19) led to an ongoing pandemic with a surge of critically ill patients. Very little is known about the occurrence and characteristic of cardiac arrest in critically ill patients with COVID-19 treated at the intensive care unit (ICU). The aim was to investigate the incidence and outcome of intensive care unit cardiac arrest (ICU-CA) in critically ill patients with COVID-19. This was a retrospective analysis of prospectively recorded data of all consecutive adult patients with COVID-19 admitted (27 February 2020–14 January 2021) at the University Medical Centre Hamburg-Eppendorf (Germany). Of 183 critically ill patients with COVID-19, 18% (n = 33) had ICU-CA. The median age of the study population was 63 (55–73) years and 66% (n = 120) were male. Demographic characteristics and comorbidities did not differ significantly between patients with and without ICU-CA. Simplified Acute Physiological Score II (SAPS II) (ICU-CA: median 44 points vs. no ICU-CA: 39 points) and Sequential Organ Failure Assessment (SOFA) score (median 12 points vs. 7 points) on admission were significantly higher in patients with ICU-CA. Acute respiratory distress syndrome (ARDS) was present in 91% (n = 30) with and in 63% (n = 94) without ICU-CA (p = 0.002). Mechanical ventilation was more common in patients with ICU-CA (97% vs. 67%). The median stay in ICU before CA was 6 (1–17) days. A total of 33% (n = 11) of ICU-CAs occurred during the first 24 h of ICU stay. The initial rhythm was non-shockable (pulseless electrical activity (PEA)/asystole) in 91% (n = 30); 94% (n = 31) had sustained return of spontaneous circulation (ROSC). The median time to ROSC was 3 (1–5) minutes. Patients with ICU-CA had significantly higher ICU mortality (61% vs. 37%). Multivariable logistic regression showed that the presence of ARDS (odds ratio (OR) 4.268, 95% confidence interval (CI) 1.211–15.036; p = 0.024) and high SAPS II (OR 1.031, 95% CI 0.997–1.065; p = 0.077) were independently associated with the occurrence of ICU-CA. A total of 18% of critically ill patients with COVID-19 suffered from a cardiac arrest within the intensive care unit. The occurrence of ICU-CA was associated with presence of ARDS and severity of illness.