Racism is enmeshed within the fabric of U.S. public education, making it critical to identify and dismantle. One way to do this is to provide professional development (PD) to teachers targeting antiracism to build awareness, decenter whiteness, and advance racial equity in schools. This systematic review is a synthesis of antiracism PD studies, summarizing the (a) topics and activities integrated, (b) participants, (c) settings, and (d) outcomes associated with participation. Thirty-eight studies published from 1981 to 2020 met study criteria. Results indicated that study participants were most likely to be white educators from urban, public elementary schools who received, on average, nearly 18 hours of professional development. Training included authentic learning and reflection opportunities, with many participants reporting increased critical consciousness and improved racial literacy after PD. However, results also illuminated (a) inconsistencies in the way white teachers responded to training, likely aligning with their own readiness to learn and racial identity development, (b) that school leadership has a key role in creating a safe, trusting, well-resourced environment for this work, and (c) white teachers may need assistance moving from talking about decentering whiteness to taking antiracist action. We conclude with implications for research, practice, and policy.