Background: The application of Extracorporeal Membrane Oxygenation(ECMO) and Extracorporeal Life support(ECLS) in hospitals is increasing. In the case of high-level skills, the volume of a specific treatment may be related to the outcome. There has been no discussion on the effect of the increasing utilization volume of ECLS in hospitals on the outcome of OHCA patients. Objectives: We want to determine how the hospital's ECMO volume affects the outcome of the overall OHCA patient visits to the hospital. Methods: We used Korean National OHCA Registry, and performed a cross-sectional study that collected adult EMS-treated cardiac origin OHCA patients between 2015 and 2019 in Seoul. We profiled the number of times ECLS, and hospitals that performed more than 20 times during the study period were regarded as high volume centers (HV centers), and the rest hospitals were defined as low volume centers (LV centers). The primary outcome was a neurologically good outcome (CPC 1 or CPC 2). The secondary outcome was survival at discharge. OHCA patients who visited the two groups were compared using a logistic regression model, and an interaction analysis was performed on the ECMO volume of the hospital and whether the patient had received ECLS. Results: Of the 17,248 included, 3,731 (21.63%) were transported to the HV center. The frequency of good neurological survival was not significant in the group transported to the HV center(aOR 1.08, 95% CI 0.9 - 1.29), but the frequency of survival to discharge was significantly higher(aOR 1.19, 95% CI 1.03 - 1.37). According to interaction analysis, OHCA patients who received ECLS at the HV center showed a significantly better neurological survival outcome(aOR 2.217, 95% CI 1.15 - 4.28), and the OHCA patients transported to the HV center, not receive ECLS had significantly better survival to discharge rates than those transported to the LV center (aOR 1.16, 95% CI 1.01 - 1.34). Conclusions: OHCA patients who were transported and received ECLS to hospitals with high ECMO volumes center had a significantly better neurological outcome. Those who were transported to the high-volume center had a better survival to discharge rate than patients transported to the low-volume one, even if they did not receive ECLS.