Abstract Brain tumour is the third leading cause of death in children and adolescents younger than 16 years of age. The increasing survival rate of these patients makes their follow-up and quality of life assessment an important task. This study evaluated the gait pathology of the patients after the combined treatment for central nervous system (CNS) tumours. It assessed if the severity of gait deviation depended on the tumour site or age of illness onset. Gait analysis was performed on patients who completed the treatment (neurosurgery, chemo- and radiotherapy) and were disease-free at the time of the study. One hundred and five patients, 42 girls and 63 boys, aged 5–24 years of age, participated in the study. Depending on the location of the tumour, patients were divided into six groups. The Gillette Gait Index (GGI) was used to quantify gait deviation of patients compared to healthy subjects. Gait analysis was undertaken using VICON 460 movement analysis system. The Helen Hayes marker set was used, together with the Vicon Plug-in-Gait model. For each child the GGI was calculated separately for the left and right legs using data extracted from the subjects’ averaged data. The results from left and right legs were then pooled together. To determine the effect of the tumour site and the onset of illness the ANOVA Kruskal–Wallis and correlation tests were used. The GGI did not depend on the tumour site, but demonstrated significant gait pathology in all patients. The age of illness onset appeared to influence the severity of gait deviation.