Bloodstream infections are severe complications in children with leukemia during chemotherapy and represent a major public health problem. The purpose of this study is to investigate patterns of bacterial and fungal bloodstream infection in children with leukemia during chemotherapy and to provide a rational basis for the use of antibiotics to reduce bacterial resistance. This study was conducted at the Centre for Hematology and Oncology of the children's Protection Teaching Hospital in the Medical City in Baghdad between January and December 2021. We registered children aged under 18 with leukemia and undergoing chemotherapy. A total of 197 bloodstream infection episodes were diagnosed in 165 children. Gram-positive bacteria are the most frequent pathogens (58%) (Staphylococcus aureus 22.8% was the predominant pathogen followed by Staphylococcus epidermidis 13.7%). Among Gram-negative isolates (38%), E. coli 15.2%was the most prevalent isolate followed by pseudomonas aeruginosa 11.7%). The most common isolate of fungi (4%) was candida. albicans 2%.During testing the bacterial pathogen to empirical antibiotics we did find multidrug resistance among bacterial groups. The Gram-positive isolates showed a high resistance rate to oxacillin (99%) and a low resistance rate to Linezolid (6%)while Gram-negative isolates exhibited( 100%) resistance to Ampicillin and the least resistance(5%) to cefoxitin. The incidence of bloodstream infection in children with leukemia is caused by multidrug-resistant organisms, without changes during different chemotherapy phases. Further study is needed to reduce this infection and antibiotic sensitivity tests are essential to avoid bacterial resistance and improve advanced therapeutic prophylaxis strategies.