The current study aimed to assess knowledge, attitudes, and practices (KAP) toward coronavirus disease 2019 (COVID-19) of persons hospitalized for psychiatric problems and the correlation between knowledge and demographics. A correlational, cross-sectional study was used to collect data through structured interviews from a convenience sample of 200 patients with psychiatric disorders seeking treatment at a psychiatric hospital using the Knowledge, Attitudes, and Practices questionnaire. Participants had poor knowledge (51.5%), moderate attitudes (75%), and low to moderate practices (61%) toward COVID-19. Knowledge was different across most demographic and illness-related variables. Global assessment of functioning and educational level predicted knowledge and accounted for 37.5% of the variance. Due to disability and poor self-care, persons hospitalized for psychiatric problems are more vulnerable to infectious diseases than the general population. Mental health nurses need to raise KAP toward COVID-19. Current results are informative to health care policymakers and mental health authorities in helping identify target populations for prevention and education about COVID-19. [Journal of Psychosocial Nursing and Mental Health Services, 60(8), 37-45.].