Thyroid dysfunction has been reported after 131I-MIBG-treatment for neuroblastoma. In this study, we have evaluated all endocrine functions from patients who were given multi-modality treatment including 131I- MIBG. Twenty-five neuroblastoma survivors who were off therapy for a median period of 6.0 years (range 1.3-11.1) were evaluated and their median age was 8.1 years (range 2.2-14.7). All patients had received 131I-MIBG, 16 chemotherapy, and 16 surgery. Fourteen patients (56%) had permanently elevated thyrotropin levels and 9 received thyroxine. Two patients had a small thyroid volume while 6 had thyroid nodules or cysts. Two boys showed hypergonadotropic hypogonadism. Growth was retarded in 39% of children. Mean Target Height Standard Deviation Score of patients with thyrotropin elevation was lower than those without (P = 0.019). Children treated for neuroblastoma with 131I-MIBG, chemotherapy and surgery were seen to be at risk from developing irreversible thyroid function loss, thyroid nodules, hypergonadotropic hypogonadism, and growth retardation. We recommend that during follow-up of neuroblastoma children, special attention should be paid to their endocrine state.