Multimodal therapy has improved survival for most childhood tumours. The development of neoplasms subsequent to therapeutic cranial irradiation is a rare but serious and potentially fatal complication. The analysis included 16 patients (pts.) with subsequent glioblastoma (SG) from several institutions in Russia who underwent cranial or neck irradiation (1 case) to treat their primary disease (acute lymphoblastic leukaemia – 12 pts., medulloblastoma – 2 pts., choroid plexus papilloma – 1 pts., lymphoma – 1 pts.). All gliomas arose within the previous radiation fields and satisfied the widely used criteria for the definition of radiation induced neoplasms. The median RT dose administered was 18 Gy with the dosage ranges being 12–55 Gy. TBI was used in one patient with Ph-positive ALL during bone marrow transplantation. Median latency period was 6 years until diagnosis of SG. The majority of SG (14 of 16) occurred during the initial 9 years of follow-up. Patients underwent surgery resection followed by standard fractionated local radiation and chemotherapy. A Kaplan–Meier analysis was used to illustrate the overall survival (OS) curves. OS rate was 34.4 ± 12.3% and 13,6 ± 9.0% at 1 and 2 years respectively with median 11 months. In case that paediatric neoplasms are treated by standard fractionated radiation or TBI is used, radiation-induced gliomas should be considered as possible long-term side effect. And the patients should be followed for a long term, even long after the period of risk for relapse of the primary cancer has passed.