AbstractLong‐term sequelae of bone marrow transplantation (BMT) are a major concern among long‐term survivors since the procedure has been considerably developed over the past decade. In this study, linear growth and growth hormone (GH) secretion were evaluated in 25 children (14 males and 11 females) with various neoplastic or non‐neoplastic hematological disorders who had survived for more than 3 years after BMT. Impaired linear growth after BMT, as defined by a change in height standard deviation score (SDS) by more than − 1.0 SD, was observed in 14 patients (56%). Four children showed severe growth suppression with a decrease in SD score by more than 2.0, and 10 exhibited a moderate reduction by between 1.0 and 2.0 SD. A recovery of normal height velocity was observed in those who had received BMT at a younger age. The type of disease, a difference in preconditioning regimen, the presence of chronic graft‐versus‐host disease or a GH secretory capacity 1 year after BMT were not contributing factors for impaired growth. A serial examination of GH secretion with insulin‐induced hypoglycemia demonstrated that poor GH secretion was not necessarily a prerequisite for impaired growth. These results indicate that the secretory status of GH does not predict the future growth pattern of children who