Objective To explore the proper and effective diagnostic strategies of diffuse sclerosing variant of papillary thyroid carcinoma.Methods Clinical data of 18 patients with diffuse sclerosing variant of papillary thyroid carcinoma who had been treated from September 2012 to September 2017 were analyzed retrospectively.Results The mean age of 18 patients was 28.5 years old,the ratio of man and woman was 1.0 to 3.5,and the neck mass (the thyroid gland diffusely enlarge) was the primary symptom of diffuse sclerosing variant of papillary thyroid carcinoma (89％,16/18);parts of patients with larger mass (3.2 to 4.5 cm) presented the sense of neck swelling (33％,6/18) or dysphagia (6％,1/18).Two patients (11％,2/18) presented hypothyroidism and hoarseness.The results of ultrasonography showed that the diffuse enlarged thyroid gland (89％,16/18),hypoechoic (78％,14/18),heterogeneous echogenicity (100％,18/18),diffuse microcalcification (89％,16/18),ill-defined tumor margin (100％,18/18) and the suspicious cervical lymph node (83％,15/18) were common features.CT scan showed that there were many suspicious cervical lymph nodes (100％,15/15).The results of fine needle aspiration cytology for the thyroid gland showed that all of the patients (100％,16/16) were diagnosed with papillary thyroid carcinoma,and cervical lymph node biopsy found lateral lymph node metastasis (100％,2/2).Postoperative pathological paraffin section indicated that most of the patients coexisted with Hashimoto thyroiditis (72％,13/18) and were found lymph node metastasis (central lymph node:89％,16/18;lateral lymph node:83％,15/18).Conclusions The young lady,the high rates of coexisting with Hashimoto thyroiditis,the diffuse enlarged thyroid gland,diffuse microcalcification and the suspicious cervical lymph node metastasis were the common features of ultrasonography in diffuse sclerosing variant of papillary thyroid carcinoma.The clinical features combined with the characteristics of ultrasonography and fine needle aspiration would be helpful for the early diagnosis and the surgery of diffuse sclerosing variant of papillary thyroid carcinoma.