Non-Hodgkin lymphoma (NHL) is the fourth most common malignancy in childhood. Thyroid nodules are identified in 1-2% of children with a history of malignancy. The most common risk factors are irradiation, female sex, iodine deficiency, puberty and prior history of thyroid disease. In children with thyroid nodules, the incidence of malignancy is higher than in adults. We report the case of an 11-year-old girl who developed papillary Ca of the thyroid after chemotherapy for NHL. The patient was diagnosed with NHL at 7-years of age and she was treated with chemotherapy until the age of 9 years (BFM 95 protocol). At 11 years of age thyroid ultrasound revealed a sonic mass sizing 1.23 x 1 x 0.68 cm with blurred margins, heterogeneous consistency, calcifications and moderate vascularity. A fine needle aspiration biopsy (FNA) revealed a papillary neoplasm. Total thyroidectomy was performed and histopathology was consistent with the diagnosis of a multi focused, diffused papillary carcinoma. Increased incidence of thyroid’s neoplasia has not been reported after chemotherapy, while irradiation is a known risk factor. The younger the age at diagnosis the higher the chance of developing a second malignancy. The patient presented developed papillary Ca of the thyroid gland 4 years post initial diagnosis of NHL raising the possibility of a second primary tumor as the definition of second malignancy implies development after at least five years from the initial diagnosis. This case signifies the necessity of systematic evaluation of the thyroid gland for children who undergo chemotherapy.