The relationship between the onset of the COVID-19 pandemic and interest in master of public health (MPH) programs is unknown. We examined trends in MPH application rates for 31 MPH concentrations and specifically for the MPH concentration in epidemiology and differences by race and ethnicity before and after the onset of the COVID-19 pandemic. We constructed a quasi-experimental design to examine trends in MPH application rates from academic years 2015-2016 through 2022-2023 by using Centralized Application Service for Schools and Programs of Public Health data. We used an interrupted time-series analysis to test whether application rates surged after the pandemic's onset (academic years 2019-2020 through 2020-2021) and whether this increase persisted during the pandemic (academic years 2020-2021 through 2022-2023). We fit models for the overall sample, a combined racially and ethnically minoritized sample, each racial and ethnic group separately, and a non-US citizen sample. The pandemic's onset correlated with an immediate increase in application rates across most samples: overall (38%) and among American Indian/Alaska Native/Native Hawaiian/Pacific Islander (91%), Asian (35%), Black (42%), Hispanic (60%), multiracial (30%), racially and ethnically minoritized (44%), and White (53%) samples. However, this trend was not sustained; application rate trends during the pandemic were significantly lower than prepandemic trends. Application rate trends for all MPH concentrations and the MPH in epidemiology concentration among non-US citizens were significantly higher during the pandemic than prepandemic. Our results highlight the need for innovative strategies to sustain MPH degree interest and a diverse applicant pool.