This study aimed at exploring the psychological challenges of Iranian English as a foreign language (EFL) learners in online courses during the pandemic. The present research had a qualitative design and used thematic analysis (TA). The participants of this study were 50 Iranian EFL students, including 31 females and 19 males, who were selected from the English translation B.A. program of the English department of Islamic Azad University, Iran. To select the participants, the convenience sampling was applied. They were students of 6th and 7th semesters. Semi-structured interviews were conducted with 50 participants of the study. Each participant was interviewed individually. The interview consisted of 15 researcher-made questions. The interviews were administered in ten one-hour sessions. Each session five participants were interviewed. The results of the present study showed that the main reasons and causes of psychological challenges perceived by the participants in online classes during the COVID-19 pandemic include on-line classes as a stress-provoking learning context, lack of digital literacy, low quality and speed of internet connection, platform issues, coronavirus disease stress, and lack of direct interactions. At the end of the paper, the implications of the study are presented.