Objective To explore the application effect of quality control early warning system in continuous blood purification treatment of critically ill children.Methods A total of 80 critically ill children who underwent continuous blood purification treatment in our hospital from January 2020 to December 2021 were randomly selected as the research object, and were randomly divided into observation group and control group.The control group received routine nursing,and the observation group received early warning system quality control on the basis of routine nursing.The duration and alarm frequency of continuous blood purification treatment,the incidence of filter coagulation in different treatment periods,the occurrence of unplanned quitting and nursing satisfaction of the two groups were compared.Results The average alarm frequency of the observation group was (8.60±3.35),which was significantly lower than that of the control group (16.52±7.41).However,the treatment duration of the observation group (32.54±6.73 h) was significantly longer than that of the control group (21.38±5.61 h).During continuous blood purification treatment,the incidence of blood coagulation in the observation group was lower than that of the control group,and the nursing satisfaction of the observation group and the control group were 92.50% and 75.00% respectively,with significant differences.Conclusions The application of quality control early warning system in the continuous blood purification treatment of critically ill children has a high clinical value,which can not only effectively reduce the alarm frequency and the incidence of filter coagulation,but also significantly prolong the treatment time,and it is worth promoting in the future treatment process.