FACTORS ASSOCIATED WITH VIETNAMESE STUDENTS’ SELF-PERCEIVED MENTAL HEALTH PROBLEMS DURING THE COVID-19 LOCKDOWN: A CROSS-SECTIONAL STUDY Abstract The COVID-19 pandemic has stated the critical importance of addressing the mental health care needs of students. With the abrupt and extensive changes brought about by the pandemic, such as lockdowns and shifts to online learning, students worldwide faced significant psychological challenges. This context led to a comprehensive study focusing on Vietnamese students, aiming to understand their perceptions of mental health amidst these unprecedented times. The research specifically targeted the initial lockdown phase, seeking to describe the prevalence of mental health issues and identify the factors contributing to these problems among students in Vietnam. By examining these aspects, the study aimed to provide insights into the mental well-being of students during a major global crisis. A cross-sectional study was conducted among 1889 students in North and South Vietnam from 30 August, 2021 to 5 September, 2021. Socio-demographic information was collected via an online survey and the SF-12 Mental Composite Score (MCS) was used to assess self-perceived mental health problems. The study results show that the prevalence of selfperceived mental health problems, defined by an MCS<1st quartile, was 21.9% (95%CI: 20%-23.8%) among students during the COVID-19 lockdown. Regression models indicated that the following factors were significantly related to self-perceived mental health problems: Female sex, not living with family, financial difficulty, decreased health status, decreased academic performance and decreased social relationships during the COVID-19 lockdown. The study showed that many factors related to student’s self-perceived mental health problems during COVID-19, affecting a significant number of students. Suggestions for teachers and university administrators were also discussed. ASEAN Journal of Psychiatry, Vol. 25 (8) October, 2024;1-9.