Objectives <p>The police killing of George Floyd on May 25, 2020, had widespread effects on American adults, and especially Black adults. Here, we investigate to what extent daily well-being of adolescents shifted systematically following the killing and assess heterogeneity at the intersection of gender and race.</p> Methods <p>We use a comparative interrupted time series design comparing within-person trends in daily fear, anger, emotional distress, and unsafety reported by a national sample of adolescents participating in a 15-day daily diary study Wave that intersected the murder (May 18-June 1, 2020; Black n = 224, White n = 153) to those of adolescents participating in ten other two-week-long daily diary Waves that did not intersect the murder (Black n = 576, White n = 410). The identifying assumption is that absent the killing, within-person slopes for given outcomes immediately following the killing would have resembled the average of respective slopes from the benchmark Waves.</p> Results <p>In the days following May 25, 2020, Black males experienced elevated fear and distress. Black females experienced elevated fear, anger, and unsafety. White females experienced elevated daily distress. There is more modest evidence of increases in daily unsafety among Black males. White males experienced minimal changes in daily well-being.</p> Conclusions <p>Daily well-being worsened in the short term especially among Black adolescents following the police killing of George Floyd. Moving beyond the dominant focus on direct and vicarious exposure to police violence, these results suggest that high-profile incidents of police violence can harm adolescents' well-being even when they are not proximate to these incidents.</p>