Abstract: Objective To explore the death status of children under 5 years old and its influencing factors in Jingning County,Gansu Province,so as to provide theoretical basis for formulating effective measures and related policies to reduce child mortality in this area.Methods Collecting the monitoring data of eight under adopt ICD-10 to classify the causes of death; Analyzing the relative factors such as mortality,composition ratio and sequence of death of children under five years old retrospectively. The monitoring data of dead children under 5 years old in Jingning County from 2010 to 2018 were collected. The international classification of diseases (ICD-10) was used to classify the causes of death,and the mortality,constituent ratio,sequence of causes of death and other related factors of children under 5 years old were retrospectively analyzed.Results From 2010 to 2018,the mortality rate of children under 5 years old in Jingning County was 7. 77‰,the infant mortality rate was 6. 07‰,and the neonatal mortality rate was 4. 29‰. The mortality rate of children under 5 years old,infant mortality and neonatal mortality showed a downward trend. The rank order of death causes of children under 5 years old were preterm birth/low birth weight,birth asphyxia,congenital heart disease,pneumonia and other congenital abnormalities. The mortality rate of children under 5 years old in rural areas was higher than that in urban areas (P<0. 05).Untreated children before death accounted for 20. 06%,and 34. 8% of children under 5 years old died on the way to medical treatment or at home.Conclusions Reducing the neonatal mortality rate is the key to reducing the mortality rate of children under 5 years of age. In order to effectively reduce the mortality rate of children under 5 years of age,it is necessary to further strengthen pre-pregnancy and prenatal health care,prenatal screening,tertiary prevention of birth defects and publicity of child health care and safety knowledge.