Abstract： Objective:To investigate the time characteristics from extracorporeal cardiopulmonary resuscitation (ECPR) initiation to termination.Methods:The data of ECPR patients in extracorporeal life support center of the First Affiliated Hospital of Nanjing Medical University from April 2015 to October 2023 were retrospectively analyzed. The patients were grouped by survival/death at 90 days, in-hospital/out-of-hospital cardiac arrest (IHCA/OHCA), daytime/evening initiation, and procedural/non-procedural termination. Data on age, sex, Charlson comorbidity index, interhospital transport, initial rhythm, ECPR initial blood gas pH and lactate value, no-flow time, time from cardiac arrest to extracorporeal membrane oxygenation (ECMO) initiation (CA-Pump On time), ECPR initiation/termination and ECMO treatment time, 90-day survival rate and so on were analyzed.Results:200 ECPR patients were enrolled, the cardiogenic etiologies were accounted for 70.5%, more men than women, 68 (34.0%) patients survived at 90 days, of whom 61 (89.7%) patients had good neurological outcomes. The 90-day survival group had a significantly lower of no-flow time, a higher proportion of IHCA and initial shockable heart rhythm, with a higher ECPR initial blood gas pH and a lower lactic acid value than those in the death group. 3. The no flow time in OHCA group was significantly longer than that in IHCA group, with a lower ECPR initial blood gas pH and a higher lactic acid value, 77.4% were non-procedural termination and the 90-day survival rate was 16.1%. ECPR were initiated in all time periods, IHCA-ECPR initiated at random, OHCA-ECPR were rare in the early morning, and the initiation time had no significant effect on ECPR outcomes. There were 75.5% of ECPR terminated at the daytime, 56.8% death cases were occurred within 3 days after ECPR, and 19.0% of patients in the procedural termination group died due to a combination of factors.Conclusions:ECPR had a potentially high benefit for patients with IHCA, initial shockable rhythm, and a short no-flow time. The ECPR initiation time were irregular and had no effect on ECPR outcomes. Death events tend to occur in the early days after ECPR, and ECPR terminated is mostly during the daytime working hours. The construction of full-time ECPR team should be strengthened.