Abstract Background: Posttraumatic stress disorder (PTSD) after a stay in the intensive care unit (ICU) can affect one in five ICU survivors. At the beginning of the coronavirus disease 2019 (COVID-19) pandemic, admission to the ICU for COVID-19 was stressful due to the severity of this disease. This study assessed whether admission to the ICU for COVID-19 was associated with a higher prevalence of PTSD compared with other causes of ICU admission after adjustment for pre-ICU psychological factors. Methods: This prospective observational comparative cohort study included 31 ICUs. Eligible patients were adult ICU survivors hospitalized during the first wave of COVID-19 pandemic in France, regardless of the reason for admission. The prevalence of substantial PTSD symptoms at 6 months was assessed using the PTSD Checklist for DSM-5 (PCL-5). Sociodemographics, clinical data, history of childhood trauma (Childhood Trauma Questionnaire [CTQ]), and exposure to potentially traumatic events (Life Events Checklist for DSM-5 [LEC-5]) were assessed. Results: Of the 778 ICU survivors with COVID-19, 417 were assigned to the COVID-19 cohort patients in the COVID-19 and non-COVID-19 cohorts, respectively. Fourteen (4.9%) and 11 (4.9%), respectively, presented with presumptive diagnosis of PTSD at 6 months (p = 0.976). After adjusting for age, sex, severity score at admission, use of invasive mechanical ventilation, ICU duration, CTQ and LEC-5, COVID-19 status was not associated with presumptive diagnosis of PTSD using the PCL-5. Only female sex was associated with presumptive diagnosis of PTSD. However, COVID-19 patients reported significantly more intrusion and avoidance symptoms than non-COVID patients (39% vs. 29%, p = 0.015 and 27% vs. 19%, p = 0.030), respectively. The median PCL-5 score was higher in the COVID-19 than non-COVID-19 cohort (9 [3, 20] vs. 4 [2, 16], p = 0.034). Conclusion: Admission to the ICU for COVID-19 was not associated with a higher prevalence of PTSD compared with admission for another cause during the first wave of the COVID-19 pandemic in France. Trial Registration: Clinicaltrials.gov Identifier NCT03991611, registered on June19, 2019