Introduction: Bystander-provided cardiopulmonary resuscitation (CRP) influences the survival rates of out-of hospital cardiac arrests (OHCAs). Disparities on bystander resuscitation measures between Black, Hispanic, Asians and Non-Hispanic White OHCAs is unclear. Examining racial and ethnic differences in bystander resuscitations is essential to better target interventions. Methods: 15,542 witnessed OHCAs were identified between April 1, 2011, and June 30, 2015 using the Resuscitation Outcomes Consortium Epidemiologic Registry 3, a multi-center, controlled trial about OHCAs in the United States and Canada. Multivariable logistic regression model was used to analyze the differences in bystander resuscitation (bystander CRP [B-CPR], CPR plus ventilation, automated external defibrillators/defibrillator application [B-AED/D], or delivery of shocks) and clinical outcomes (death at the scene or en route, return of spontaneous circulation upon first arrival at the emergency department [ROSC-ED], survival until ED discharge [S-ED], survival until hospital discharge [S-HOS], and favorable neurological outcome at discharge) between Black, Hispanic, or Asian victims and Non-Hispanic White victims. Results: Compared to OHCA victims in Non-Hispanic Whites, Black, Hispanic, and Asians were less likely to receive B-CPR (adjusted OR: 0.79; 95 % CI: 0.63-0.99), and B-AED/D (adjusted OR: 0.80; 95 % CI: 0.65-0.98) in public locations. And, Black, Hispanic, and Asian OHCAs were less likely to receive bystander resuscitation in street/highway locations and public buildings, and less likely to have better clinical outcomes, including ROSCED, S-ED and S-HOS. Conclusion: Black, Hispanic and Asian victims with witnessed OHCAs are less likely to receive bystander resuscitation and more likely to get worse outcomes than Non-Hispanic White victims.