Abstract： Objective To survey on the condition of critically ill children in emergency room (ER) for improving the care for them.Methods Data of 374 critically ill children in emergency intensive care unit (EICU) were recorded in the respects of mode of sending them to ER,rescue during transport,length of stay in ER,blood gas,electrolytes,accuracy of assessing pediatric critical illness score/neonate critical illness score (PCIS/NCIS) and Glasgow Coma Scale (GCS),correctness of determining SIRS,sepsis and septic shock.Results Of 374 patients,neonates were 29.9％,and the mean age of children patients not including neonate was 37.4 months.The mean length of ER stay was 4.7 hours (0.42-96 hours).Of 374 patients,those with infection diseases were 47.6％,and the main vehicles for transportation of patient sent to ER were Taxi (38.3％),ambulance (28.4％) and private cars (21.5％).Total fatality was 12.3％ and ER fatality ( 15.6％ ) was higher than in - hospital fatality ( 10.3％,P ＜0.01 ).The mean PCIS/NCIS of 374 patients were 81.92 ± 9.66,and the PCIS/NCIS ≤ 90 accounted for 81％.Of assessed GCSs of 172 patients,GCS≤8,GCS 9-12 and GCS 13-15 accounted for 35.5％,21.5％ and 43.0％ respectively,and fatalities were 26.23％,10.81％ and 5.41％ correspondingly (P ＜0.01 ).The PCIS values of GCS≤8 and GCS 9-12 patients were lower than those of GCS 13-15 patients (P ＜ 0.01 ).There was no significant difference in PCIS between GCS≤8 and GCS 9-12 ( P ＞ 0.05 ).PCIS and GCS were positively correlated (r=0.454,P=0.01).Of374 patients,41.7％ had SIRS,and 25.7％ had sepsis.Of 262 children not including neonates,43.5％ had shock,and 61.4％ of these shock children were septic shock.In 374 patients,those with hyponatremia accounted for 37.2％,and those with hyperkaliemia accounted for 22.0％.The rate of hypoglycemia found in neonates was 20.91％ and rate of hyperglycemia occurred in neonates was 29.1％.The rate of hypoglycemia found in children patients was 9％ and hyperglycemia was 66.7％.Patients with pH ＜ 7.35 accounted for 67.8％ and those with pH ＜ 7.2 were 33.1％.Conclusions The majority of children patients in pediatric ER were neonates and infants.The length of ER stay was short with mean value of 4.7 hours (0.42-96 hours).ER fatality was higher than in - hospital fatality,suggesting the critically ill children patients should be admitted as early as possible.The rate of using ambulance was only 28.4％.The Emergency Medical Service (EMS) should be improved to enhance the public sense of the EMS available.PCIS/NCIS can be used in ER for assessing the conditions and prognosis of critically ill children.GCS ≤8 and GCS 8-12 patients accounted for 57％ with majority of nontrauma brain injury.The values of PCIS in GCS≤8 and GCS 9-12 patients were much lower than those in GCS 13-15 patients.Patients with GCS ＜ 13 might be in critical settings.Majority of shock patients were septic shock (61.4％).Hyponatremia,hyperkalemia,hyperglycemia and hypoglycemia often occurred in critically ill pediatric patients and hypoglycemia not excepted in the neonates should have attention paid to.The main factor of acid -base balance disorder in critically ill children was acidosis (67.8％).