Abstract
Before the COVID-19 pandemic, research has focused considerably on employees' mental health because of the great ways it affects organizational outcomes. COVID-19 presented adverse situations in the economy and experiences that threatened employees' mental health, suggesting an increased level of depression, anxiety, and stress. This study investigated the prevalence and the factors predicting depression, anxiety, and stress among the employee population in Nigeria. The study utilized a cross-sectional approach using a descriptive survey research design in a sample of 3,950 employees from public and private organizations. A demographic questionnaire and the 21-item depression, anxiety, and stress scale (DASS-21) were used to collect data for the study. Mean, standard deviation, frequency, regression analysis, and Chi-square were used to analyze data. The result showed high levels of anxiety and stress and a moderate level of depression among employees in Nigeria. 90.51% of employees had moderate to high levels of anxiety, 51.52% of the employees had high and or moderate levels of depressive symptoms, while 94.13% of employees had moderate to high levels of stress. Job type, employer, and location accounted for significant differences in depressive symptoms, anxiety, and stress. It is concluded that there is a high prevalence of depression, anxiety, and stress due to the COVID-19 pandemic, necessitating reinforced mental health services among employees.