BACKGROUND: The coincidence of autoimmune thyroiditis (AIT) in patients with papillary thyroid carcinoma (PTC) is ranging between 10 and 58% in the general population. MATERIAL AND METHODS: In the present study retrospective ultrasound, clinical and autoimmune assessment of 24 patients diagnosed with papillary thyroid carcinoma between 2000-2016 was performed. RESULTS: The coexistence of PTC and AIT was found in 50% of patients with PTC. Patients were divided into two groups. PTC AIT (+) group involved 12 children at the mean age 14.9 years (range 11-20 years, 9 girls) and PTC AIT (-) 12 children at the mean age 12.9 years (range 7-18 years, 5 girls). Papillary thyroid microcarcinoma (PTMC) was diagnosed in 6 patients (in 5 with AIT). US characteristics of PTC was heterogenous: hypoechogenic with/without increased vascularisation, normoechogenic with halo, with/without microcalcifications. In 70% PTC AIT (+) and in all PTC AIT (-) patients ultrasound analysis revealed that the thyroid tissue of the whole gland was normoechogenic. Local metastases in lymph nodes were found in 40% of PTMC AIT (+). CONCLUSION: Lack of increased vascularization and microcalcifications and presence of``halo`in the nodule does not exclude malignancy. Due to the presence of lymph node involvement in PTMC in all children with PTC total thyroidectomy should be performed with lymph nodes verification.