Objective To investigate demographic disparities in prehospital cardiopulmonary resuscitation (CPR) initiation and successful outcomes of patients with out-of-hospital cardiac arrest (OHCA) treated by emergency medical services (EMS) providers. Methods We analyzed the National Emergency Medical Service Information Systems (NEMSIS) 2017 database, analyzing patient gender, age and race against CPR initiation and Return of Spontaneous Circulation (ROSC). The analysis was performed for a subset of patients who received bystander interventions (n = 3,362), then repeated for the whole cohort of patients (n = 5,833). Results Within the subgroup of patients that received CPR or AED application prior to the arrival of the paramedics, a logistic regression for CPR initiation rates as a function of race, gender and age reported the following adjusted odds ratios: African American (AA) to White 0.570 (95%CI [0.419, 0.775]), Hispanic to White 0.735 (95%CI [0.470, 1.150]); female to male 0.768 (95%CI [0.598, 0.986]); senior to adult 0.708 (95%CI [0.545, 0.920). Similarly, a logistic regression of ROSC as a function of race, gender and age reported the following adjusted odds ratios: AA to White 0.652 (95%CI [0.533, 0.797]) Hispanic to White 1.018 (95%CI [0.783, 1.323]); female to male 0.887 (95%CI [0.767, 1.025]); senior to adult 0.817 (95%CI [0.709, 0.940]). Similar trends existed in the entire cohort of patients. Conclusions These results suggest that there are discrepancies in patient care during cardiopulmonary arrest performed by EMS for OHCA, inviting further exploration of healthcare differences in the prehospital EMS approach to OHCA.