OBJECTIVE : To investigate the correlations of ultrasound and pathological characteristics of thyroid carcinoma through evaluating the messenger ribonucleic acid (mRNA) level and protein expression of thyroid cancer-1 (TC-1). METHODS : The patients with papillary thyroid carcinoma (PTC) hospitalized in our hospital were enrolled. Then, real-time fluorescence quantitative polymerase chain reaction (qPCR) and immunohistochemistry (IHC) streptavidin-peroxidase (SP) technique were applied to measure the mRNA and protein expression levels of TC-1 in PTC and corresponding adjacent tissues (NCE) of 50 patients. The relations with clinicopathological and ultrasound characteristics were analyzed. RESULTS : The expression of TC-1 mRNA in PTC tissues was statistically higher than that in corresponding adjacent tissues and significantly correlated with tumor-node-metastasis (TNM) stage, pathological grade, and lymph node metastasis of PTC (p<0.05). According to IHC, TC-1 positive expression was mainly found in the cytoplasm in PTC samples, which was statistically increased compared to adjacent tissues (p<0.05). Western blotting results revealed that the relative protein expression of TC-1 in PTC tissues was 2.646±195, which was significantly higher than that in corresponding adjacent tissues (892±76) (p<0.05). The TC-1 protein expression also showed significant associations with TNM stage, pathological grade, and lymph node metastasis of patients (p<0.05). The level of TC-1 mRNA in PTC tissues with micro-calcification detected by ultrasound (87.46±49.55) was higher than that in those without micro-calcification (38.46±29.15) (p<0.05). CONCLUSIONS : The expression of TC-1 plays an important role in the occurrence and development of PTC. Ultrasound characteristics reflect the expression of TC-1 in PTC tissues to some extent, providing a certain value in evaluating the prognosis of PTC.