All cases of thyroid cancer in children aged 15 years or younger registered in Norway (1953-1987) are presented. 30 girls and 5 boys are included, the youngest being a 6-year-old boy. Half of the patients were in the age-group 14-15 years. As for adults, papillary thyroid cancer was most common. 70% of the patients presented with tumour growth outside the thyroid gland. In spite of this, only 2 children died of the disease during the follow-time (maximum 37 years).