Abstract: Objectives To investigate the pathogen and clinical features in the pediatric acute lymphoblastic leukemia(ALL) patients with septicemia with positive blood cultures episodes. Methods A total of 145septicemia with positive blood cultures episodes in 112 of 545 pediatric ALL patients since April, 2008 to December, 2014 were included. And the clinical manifestations, morbidity, timing of septicemia, site of infection, pathogen characteristics, drug susceptibility rates, related factors for septicemia, treatment and outcomes were retrospectively analyzed. Results The morbidity of 545 pediatric ALL patientwith septicemia was 20.55%. The  septicemia onset was mostly during the induction course in chemotherapy in the Standard risk and Intermediate risk ALL groups, and  the consolidation course in chemotherapy in the high risk ALL groups. The infection were the most commonly seen inrespiratory tract and gastrointestinal tract. Among 149 strains of pathogens isolated from the patients, Gram-positive bacteria contribute the 51.68% (77/149) strains while 70 strains (47.98%) were Gram-negative bacteria. The incidence rate of septicemia was significantly increased in the patients of High risk ALL groups, central venous catheter, the neutrophil count below 0.1×109/L  and the duration of neutropenia more than 7 days (P