BACKGROUND: The coronavirus infection of 2019 (COVID-19) produced an incontestable impact on the mental health of people around the world. This impact is conditioned by a complex interrelation of social, cultural, economic and COVID-19-associated factors. However, insufficient data on comparison of parameters of mental health of the population in different countries limits our understanding of these interrelations. AIM: To evaluate and compare the frequency of mental health disorders (general problems and problems related to COVID-19) and their correlations in four countries: Albania, India, Iran and Nigeria. MATERIALS AND METHODS: In this study, the problems of mental health of the population of four countries (Albania, India, Iran and Nigeria) were investigated. The participants were selected in the period from July 07, 2020 to November 13, 2020. The study used a cross-check anonymous online questioning to assess the degree of depression, anxiety and insomnia, which included Patient Health Questionnaire (PHQ-9), Generalized Anxiety Disorder 7 (GAD-7) questionnaire and Insomnia Severity Index (ISI). To assess the mental health problems associated with COVID-19, the survey included Corona Anxiety Scale (CAS), Obsession with COVID-19 Scale (OCS) and Fear of COVID-19 Scale (FCV-19S). To analyze the data, ꭓ2, KruskalWallis tests and multiple linear regression were used. RESULTS: In general, the prevalence of general anxiety, depression, insomnia and COVID-19-associated anxiety, was higher among the Iranian population compared to the other three countries. Risk factors for increased anxiety about the new coronavirus infection were fear, depression, trouble and age; however, these factors were different in the four studied countries. The parameter was highest (47%) in the Albanian population and lowest (20%) in India. CONCLUSIONS: This study shows different prevalence of psychological health disorders during the ongoing pandemics, including problems associated with COVID-19, in different countries. Therefore, healthcare policy and measures adopted in different countries, should be adapted to specific needs of the country rather than be based on the universal global responsive measures.