Background: Erectile dysfunction (ED) is suspected to be the symptom manifestation of COVID-19.However, scarce data was presented this day. Our study was conducted to determine the prevalence of ED and its associated factors among Thai patients with COVID-19.Methods: Sexually active males with COVID-19, hospitalized between May and July 2021 at one university hospital in Bangkok, were screened for erectile dysfunction by the International Index of Erectile Function 5 (IIEF-5). Demographic data and COVID-19 treatment history were collected. Mental health status, including depression and anxiety, was evaluated with the Thai Patient Health Questionnaire 9 (PHQ-9) and the Generalized Anxiety Disorder Scale (GAD-7), respectively. The sample size was calculated, and logistic regression was used to analyze the association.Results: One hundred fifty-three men with COVID-19 were recruited. ED prevalence was 64.7%, of which severity was mostly mild. Logistic regression, adjusted for age, BMI, and medical comorbidities, portrayed a significant association between ED and mental health status. Higher risk of ED was found in participants with major depression [adjusted OR 8.45, 95% CI: 1.01-70.96, P=0.049] and higher GAD-7 total score [adjusted OR 1.15, 95% CI: 1.01-1.31, P=0.039].Conclusions: Thai patients with COVID-19 had high prevalence of ED, which was associated with mental disorders. Thus, screening for mental problems is recommended in individuals with COVID-19 and ED.