This study evaluated factors linked with perceived stress related to the COVID-19 pandemic and lockdown and addictive behaviors prior to and during lockdown in a sample of students who indicated engaging in alcohol consumption behaviors before lockdown. Methods: Cross-sectional study. French students from four universities participated in this study, and 2,760 students reported alcohol use. During the first week of lockdown, students reported their perceived levels of stress regarding COVID-19. Substance use and addictive behaviors were reported before and during lockdown, and media exposure, demographical, living conditions, and environmental stressors were reported during lockdown. Results: Women reported greater levels of stress (95% CI: 1.18 to 1.93, p < 0.001). Highly-stressed students also report less social support (95% CI: -1.04 to -0.39, p < 0.001) and were more likely to worry ...