BACKGROUND Primary brain tumors are the most common solid tumors in children. Surgery is the basis of treatment for these patients, who require postoperative admission to the ICU-P. The aim of this study was to at the epidemiology of brain tumors of patients admitted to our ICU-P and to analyze the progress of these children in the postoperative period. METHODS Retrospective-prospective study of children admitted to our unit after brain tumor surgery between January 1998 and January 2007. We collected information such as, personal details, clinical characteristics, type of intervention and postoperative period. RESULTS We reviewed 161 postoperative periods, corresponding to 134 patients (54.5% male). The mean age was 7 years and 8 months +/- 5 months. The most common location was the posterior fossa (44.8%). The most common histological type was low grade/intermediate astrocytoma (44.7%). The most frequent complication was diabetes insipidus (9.9%). Resection was complete in 58.4% patients. The median stay in the ICU-P was 2 days (0-61 days). 3 patients died after surgery. CONCLUSIONS The epidemiology of the group of patients admitted to our ICU-P is similar to the general population. The most common complication is diabetes insipidus.