Objectives To evaluate disparities in youth e-cigarette use patterns and flavor use by race/ethnicity over time. Methods We used data from the US 2014-2019 National Youth Tobacco Survey (NYTS) to examine trends in dual use (co-use of e-cigarettes and cigarettes or other tobacco products), occasional (≤ 5 days) versus frequent use (≥ 20 days) in the past 30 days, and flavor use among current (past-30-day) e-cigarette users (n = 13 178) across racial/ethnic groups (non-Hispanic Whites, non-Hispanic Blacks, Hispanics/Latinos, and non-Hispanic others). Results Among current e-cigarette users, dual use and occasional use decreased significantly from 2014 to 2019 across racial and ethnic groups except for non-Hispanic Blacks; frequent use and flavored e-cigarette use increased among non-Hispanic Whites, Hispanics/Latinos, and non-Hispanic others but not among non-Hispanic Blacks. In 2019, non-Hispanic Black e-cigarette users were more likely to report dual use (adjusted odds ratio [AOR] = 2.2; 95% confidence interval [CI] = 1.5, 3.2; P < .001) and occasional use of e-cigarettes (AOR = 3.7; 95% CI = 2.3, 5.9; P < .001) but less likely to report frequent use (AOR = 0.2; 95% CI = 0.1, 0.4; P < .001) and flavored e-cigarette use (AOR = 0.4; 95% CI = 0.3, 0.5; P < .001) than their White peers. Conclusions Youth e-cigarette use patterns differed considerably across racial/ethnic groups, and tailored strategies to address disparities in e-cigarette use are needed. (Am J Public Health. 2021;111(11):2050-2058. https://doi.org/10.2105/AJPH.2021.306448).