Objective: There is continued interest in understanding what leads people to engage in CDC-recommended COVID-19 prevention behaviors. We tested whether fear and COVID-19 worry would replicate as the primary drivers of six CDC recommended prevention behaviors. Methods and Measures: We recruited 741 adult participants during the second major peak of the COVID-19 pandemic in the United States (early 2021). Using very similar methods to the original study, participants completed a 10-day daily diary. Mixed effects models identified the strongest predictors of each individual prevention behavior as well as approach and avoidance behavior clusters. Results: At the between-person level, COVID-19 worry, COVID-19 perceived susceptibility, fear, and positive emotions all had positive zero-order associations with the prevention behaviors. However, with all predictors in the same model together, primarily COVID-19 worry remained significant for both the individual behaviors and behavior clusters. At the within-person level, only fear related to assessing oneself for COVID-19 and approach behaviors on the same day, but not the next day. Mediational analyses suggested COVID-19 worry, but not COVID-19 susceptibility, mediated the links between fear and approach/avoidance behaviors. Conclusion: Findings replicated worry about yourself or a loved one getting COVID-19 as the strongest predictor of prevention behaviors.