Over the past few decades, schools in the U.S. have increasingly relied on school resource officers (SROs) to provide safety and order within school settings. In spite of the intuitive appeal that SROs might offer for making schools safer, critics suggest that there may be unintended negative consequences to this trend, including an increase in exclusionary discipline (i.e., suspensions and expulsions) of students in schools with SROs. This study presents a synthesis of the existing quasi-experimental literature examining the relationship between the presence of SROs and exclusionary discipline in U.S. high schools. Following a systematic literature search, random effects meta-analysis was used to summarize ten effect sizes from seven reports. One meta-analytic model with seven effect sizes achieved statistical significance, yielding a mean rate ratio of 1.21, 95 % CI (1.04, 1.40), indicating that the presence of SROs in high schools was associated with higher rates of exclusionary discipline. A second metaanalytic model with three effect sizes indicated no statistically significant relationship between SRO presence and rates of exclusionary discipline [rate ratio = 1.54, 95 % CI (0.78, 3.06)]. There were high levels of heterogeneity in both models, indicating that unmeasured moderating variables would likely explain some of the variance. Implications for research are discussed.