Background: Survivors of critical care may demonstrate mental health disorders in the months after discharge. Research question: What are risk factors for mental health disorders after ICU discharge and is there an association between the burden of mental illness and health-related quality of life (HRQoL)? Study design and methods: Multicenter prospective cohort study that included 579 adult ICU survivors with an ICU stay of > 72 h in 10 ICUs. Results: The outcomes were anxiety and depression assessed by the Hospital Anxiety and Depression Scale, posttraumatic stress disorder (PTSD) assessed by the Impact Event Scale 6, and HRQoL assessed by the Short Form 12 version 2. The 6-month prevalences of any mental health disorder were 36.2% (the prevalences of anxiety, depression, and PTSD were 24.2%, 20.9%, and 15.4%, respectively). ICU survivors with mental health disorders showed worse HRQoL scores in both physical and mental dimensions than those without. The higher the number of psychiatric syndromes manifested, the worse the mental dimension of HRQoL. Age of < 65 years (P = .009), history of depression (P = .009), anxiety (P = .003) and depression (P = .02) symptoms at ICU discharge, physical dependence (P = .01), and decreased physical functional status (P = .04) at 6 months were associated with anxiety. History of depression (P = .001), depression symptoms at ICU discharge (P < .001), and decreased physical functional status at 6 months (P = .01) were associated with depression. Depression symptoms at ICU discharge (P = .01), physical dependence (P = .01), and decreased physical functional status (P = .02) at 6 months were associated with PTSD. Interpretation: The network of potential risk factors for mental illness among patients discharged from an ICU is complex and involves multiple factors (age, premorbid mental health, acute emotional stress, and physical impairment after ICU stay). The negative impact of the burden of mental illness on HRQoL among critical care survivors is of concern.