To investigate the clinical characteristics and risk factors of acute leukemia complicated with multi-drug resistant bacterial septicemia in children. The clinical data of children with acute leukemia complicated with septicemia admitted to the Affiliated Hospital of Guangdong Medical University from January 2013 to May 2021 were retrospectively analyzed. Their flora composition and drug resistance were also analyzed. The children were divided into multi-drug resistant bacteria (MDRB) group and non-multi-drug resistant bacteria (non-MDRB) group according to the drug sensitivity results, and the differences in clinical data between the two group were compared. A total of 108 children had drug sensitivity results, 47 cases in the MDRB group, including 26 strians of Gram-positive bacteria (G+), the most common multi-drug resistant G+ bacteria were coagulase-negative staphylococci (CoNS) and Staphylococcus aureus, and the most common multi-drug resistant Gram-negative bacteria G- bacteria were Escherichia coli and Klebsiella pneumoniae subspecies pneumoniae. Compared with non-MDRB group, children in MDRB group had higher C-reactive protein (CRP) level and mortality rate (P <0.001, P =0.009), lower initial empirical anti-infection efficiency (P <0.001), and were more likely to have septic shock (P =0.003). Logistic analysis showed that the risk factors of acute leukemia complicated with MDRB septicemia in children were previous MDRB infection (OR =6.763, 95% CI: 1.141-40.092, P =0.035), duration of agranulocytosis before infection≥7 days (OR =3.071, 95% CI: 1.139-8.282, P =0.027), and previous use of antimicrobial drugs within 90 days before infection (OR =7.675, 95% CI: 1.581-37.261, P =0.011). The clinical features of acute leukemia complicated with MDRB septicemia in children include a heavy inflammatory response, significantly elevated CRP, susceptibility to secondary septic shock, low efficiency of initial empirical anti-infective therapy, and high mortality rate. Previous MDRB infection, duration of agranulocytosis before infection≥7 days, and previous use of antimicrobial drugs within 90 days before infection are risk factors of acute leukemia complicated with MDRB septicemia in children.