Pre- and Post-Pandemic (COVID-19) Mental Health of International Students: Data from a Longitudinal Study

International students are highly vulnerable to the risk of mental health worsening before and during the pandemic (COVID-19). This study investigated international students' mental health pre- and post-pandemic (COVID-19). It is a longitudinal study, and data were collected online, pre-pandemic (N = 470) and during the pandemic (N = 420). Using a random sampling technique, a self-administered questionnaire was used to measure mental health, including depression and anxiety. Findings show that international students' mental health was good in pre-pandemic. Meanwhile, international students were found to be more depressed and anxious during the pandemic. Findings also investigated that in the pre-pandemic phase, young students' and mainly females' mental health was worsened. This study concluded that students' mental problems are alarming, so the university should provide psychological services for the student's mental health. Post-pandemic is leaving long-lasting psychological effects and will require further investigation.