Objective: This study aimed to explore the prevalence of psychological disorders and associated factors at different stages of the COVID-19 epidemic in China. Methods: The mental health status of respondents was assessed via the Patient Health Questionnaire-9 (PHQ-9), Insomnia Severity Index (ISI) and the Generalized Anxiety Disorder 7 (GAD-7) scale. Results: 5657 individuals participated in this study. History of chronic disease was a common risk factor for severe present depression (OR 2.2, 95% confidence interval [CI], 1.82-2.66, p < 0.001), anxiety (OR 2.41, 95% CI, 1.97-2.95, p < 0.001), and insomnia (OR 2.33, 95% CI, 1.83-2.95, p < 0.001) in the survey population. Female respondents had a higher risk of depression (OR 1.61, 95% CI, 1.39-1.87, p < 0.001) and anxiety (OR 1.35, 95% CI, 1.15-1.57, p < 0.001) than males. Among the medical workers, confirmed or suspected positive COVID-19 infection as associated with higher scores for depression (confirmed, OR 1.87; suspected, OR 4.13), anxiety (confirmed, OR 3.05; suspected, OR 3.07), and insomnia (confirmed, OR 3.46; suspected, OR 4.71). Limitation: The cross-sectional design of present study presents inference about causality. The present psychological assessment was based on an online survey and on self-report tools, albeit using established instruments. We cannot estimate the participation rate, since we cannot know how many potential subjects received and opened the link for the survey. Conclusions: Females, non-medical workers and those with a history of chronic diseases have had higher risks for depression, insomnia, and anxiety. Positive COVID-19 infection status was associated with higher risk of depression, insomnia, and anxiety in medical workers.