To investigate the status of cardiopulmonary resuscitation (CPR) in patients with sudden cardiac arrest (CA) in the emergency department. A multicenter prospective observational study was conducted. The patients with CA admitted to 13 hospitals from 6 provinces in four different regions, including North China, Southern China, East China, Southwest China, from July 1st, 2015 to July 31st, 2017 were enrolled. A modified Utstein template was applied to collect clinical data, including general data, CA related data and prognosis, and primary outcome indicator was the return of spontaneous circulation (ROSC) rate, and the secondary outcome indicator was 28-day survival rate. The influence factors of ROSC were screened by Logistic regression analysis. The data of 613 patients with CA in 13 hospitals were enrolled. The ROSC rate in Beijing and Guangdong Province was higher, but there was no significant difference in 28-day survival rate among hospitals from different provinces. (1) In 613 patients with CA, there were 413 patients suffering from in-hospital cardiac arrest (IHCA, 67.4%), and 200 suffering from out-hospital cardiac arrest (OHCA, 32.6%). 208 patients had ROSC at least once (33.9%), only 20 patients survived within 28 days (3.3%). ROSC rate in IHCA patients was significantly higher than that in OHCA patients [37.3% (154/413) vs. 27.0% (54/200), P < 0.01]. There was no statistic difference in 28-day survival rate between patients with IHCA and OHCA. The patients received manual chest compression, electric defibrillation, or epinephrine ≤ 4 mg had higher ROSC rate, but 28-day survival rate showed no significant difference. Multivariate Logistic regression analysis showed that IHCA [odds ratio (OR) = 1.893, 95% confidence interval (95%CI) = 1.253-2.858, P = 0.002], manual chest compression (OR = 0.506, 95%CI = 0.348-0.736, P = 0.000), electric defibrillation (OR = 0.458, 95%CI = 0.300-0.699, P = 0.000), and total adrenalin ≤ 4 mg (OR = 0.317, 95%CI = 0.216-0.464, P = 0.000) were the protective factors of ROSC in CA patients. (2) In 200 OHCA patients, there were 49 patients had ROSC (24.5%), only 5 patients survived (2.5%). The patients aging < 65 years, with witnesses of CPR, received manual chest compression, electric defibrillation, or epinephrine ≤ 4 mg had higher ROSC rate, and the ROSC rate was higher in ambulances than that at home and in public sites, but 28-day survival rate showed no significant difference. Multivariable Logistic regression analysis showed that age < 65 years old (OR = 2.749, 95%CI = 1.192-6.336, P = 0.018), manual chest compressions (OR = 0.196, 95%CI = 0.072-0.535, P = 0.001), electric defibrillation (OR = 0.263, 95%CI = 0.108-0.641, P = 0.003), total adrenaline dose ≤ 4 mg (OR = 0.122, 95%CI = 0.049-0.303, P = 0.000) and the ambulance CA (OR = 2.441, 95%CI = 1.334-4.468, P = 0.004) were protective factors of ROSC in OHCA patients. The survival of sudden CA in emergency department was still poor. Early electric defibrillation, manual chest compression, CA occurred in hospital or in ambulance, and witness CPR can improve the ROSC rate of CA patients. Excessive use of adrenaline is not beneficial to patients with CA. NCT01987245.