Abstract: ob＜x＞jective To measure the change of the level of glial fibrillary acidic protein(GFAP) ,myelin basic protein（MBP）,S100β protein in serum with Sepsis associated encephalopathy,and to study its clinical application value in the early recognition and severity evaluation of sepsis associated encephalopathy. Methods According to the diagnostic criteria of sepsis（In line with the 2015 edition of the diagnostic criteria for sepsis in children）, PICU 80 children with sepsis admitted to Xuzhou Children’s Hospital,xuzhou Medical University from January 2018 to January 2020 were selected as the study subjects. They were divided into the SAE group (40 cases) , the Non-SAE group (40 cases). and Forty healthy children were selected as the control group. Children in the SAE group were assessed with Glasgow Coma Scale (GCS) and Full Outline of UnResponsiveness (FOUR) . The changes of serum GFAP, MBP and S100 protein levels in children into the ICU within 1 hour, 3 days after treatment and 5 days after treatment were detected by ELISA and compared. The SAE group was divided into two groups according to the degree of consciousness disturbance of the children, light (fuzzy consciousness group) and heavy (coma group), serum GFAP, MBP and S100 protein levels were compared between the two groups. The correlation between GFAP, MBP, S100 levels and Glasgow coma score (GCS) and total nonreactivity scale (FOUR) was observed. Results The serum levels of GFAP, MBP and S100 protein in the SAE group were significantly higher than those in the non-SAE group and the control group within 1 hour after into the ICU (P <0.05). The serum levels of GFAP, MBP and S100 in the coma group were significantly higher than those in the fuzzy consciousness group (P <0.05); The serum levels of GFAP, MBP and S100 protein in the SAE group were higher than those in the non-SAE group 3 days after treatment (P <0.05); The serum levels of GFAP, MBP and S100 protein in SAE group at 5 days after treatment showed no significant difference compared with non-SAE(P >0.05). The levels of GFAP, MBP and S100 protein were negatively correlated with the Glasgow coma score (GCS) and the overall nonreactivity scale (FOUR). Conclusion Serum GFAP, MBP, S100 protein help in the early identification of SAE, The assessment of the severity of SAE was positive, For evaluation of the severity of disease has the positive significance.