Being in a pandemic situation can cause psychological distress to people, which can lead to sleep disorders. The present study aimed to assess prevalence of depression, anxiety, and insomnia among Iranian people and their relations with COVID-19 fear in the early stages of COVID-19 pandemic. We created an online form and used Fear of COVID-19 scale (FCV-19), Generalized Anxiety Disorder 2 scale (GAD-2), Patient Health Questionnaire-2 (PHQ-2), and Insomnia Severity Index (ISI), to assess fear of COVID-19, anxiety, depression, and insomnia, respectively.