Invasive fungal infections (IFI) are an important cause of mortality and morbidity in patients with hematological malignancy. This study aims to investigate the incidence of IFI development, risk factors, the management of the infection in a pediatric patient group followed up with the diagnosis of acute lymphoblastic leukemia (ALL), and to share the experience obtained from a single center. Two hundred forty children monitored with the diagnosis of ALL in the pediatric hematology-oncology department of the Erciyes University Medical Faculty from January 2010 to September 2017 included in the study. A total of 30 (14 females and 14 males) IR attacks were diagnosed (12.5%) in the included patients with ALL, two of them having the attacks twice. Candida species were the dominant cause of infection (n= 17) and the rest (n= 8) had invasive Aspergillosis. Nineteen IFI attacks were assessed as proven, 6 as probable, and 5 as possible IFI. The most fungal infection was detected in blood culture (43.3%) followed by pulmonary involvement (40%). The most frequently used diagnostic methods were direct microscopic examination, histological examination, and cultures (66.6%). IFI-related mortality was 20%. IFI continues to be an important problem in pediatric patients with hematologic malignity. The 7 of the observed invasive Aspergillosis developed in non hepafiltered room. Treatment of neutropenic children in hepafiltered rooms decrease the risk of IFI. With careful assessment of the patients bearing risk factors for IFI development, early diagnosis and treatment will reduce morbidity and mortality.