Respiratory failure (RF) is a main cause of pediatric intensive care unit (PICU) admission in children with hemato-oncological diseases. We present a retrospective chart review of children admitted to our PICU because of RF (January 2006 to December 2010). The aims of this study are the following: (1) to describe the demographical and clinical characteristics and respiratory management of these children; and (2) to identify the factors associated with mechanical ventilation (MV) and mortality. A total of 69 patients, encompassing 88 episodes, were included (55/88 cases were hypoxemic RF). The first respiratory support at PICU admission was, in decreasing order of frequency, high-flow oxygen nasal cannula (HFNC; 50/88), noninvasive ventilation (NIV; 13/88), and oxygen nasal cannula (16/88). MV was necessary in 47/88 episodes, 38/47 after another respiratory support. In 18/28 children with initial NIV, MV was required later. MV was associated with O-PRISM score, NIV requirement, suspected respiratory infection, and days of PICU treatment. Patients without MV showed an increased survival rate (P=0.001). In summary, the hypoxemic RF was the main cause of PICU admission, and HFNC or NIV was almost always the first respiratory support. The use of MV was associated with a higher mortality rate. The utility of precocious HFNC or NIV should be investigated in larger clinical studies.