Objective: This article tests the substance use behaviors of college students before and during COVID-19 pandemic. Methods: In-depth assessment and nightly survey data was used from a longitudinal study (n = 675) which examined student substance use during the 2019-2020 academic year, both before and during the onset of the COVID-19 pandemic. Changes in beer/wine, tobacco, liquor, and marijuana use before "versus" during the pandemic, in addition to the interaction of COVID-19, were tested with gender and subjective social status. Results: Marijuana use significantly decreased from a weekly prevalence of 9.9% before COVID-19 to 6.4% during COVID-19 (p = 0.002). A similar decrease was seen in liquor use (10.6% before COVID to 6.4% during COVID, p = 0.01). There was no significant change observed for beer/wine use or for tobacco use. Conclusion: In the wake of the COVID-19 pandemic, liquor, and marijuana use decreased for college students, while other substance use stayed the same.