Objective To investigate the expression level of CK2α in thyroid carcinoma, and to evaluate the biological function and its mechanism of CK2α in thyroid carcinoma. Methods Twenty pairs of clinical thyroid carcinoma tissues and corresponding paracancerous normal tissues were obtained, and the expression of CK2α in thyroid carcinoma tissues and different human thyroid cancer cell lines were detected by qRT⁃PCR analysis. The effect of CK2α on cell proliferation of thyroid cancer cells was detected by CKK⁃8 method. The effects of CK2α on the migration and invasion of thyroid cancer cells were detected by wound healling test and Transwell test. The qRT⁃PCR was used to analyze the relationship between CK2α and YBX1 expression. Results CK2α was significantly up⁃regulated in thyroid carcinoma tissues and cell lines. In addition, decreased CK2α expression significantly inhibited the proliferation, migration and invasion of thyroid cancer cells, whereas overexpression of CK2α promoted the proliferation, migration and invasion of thyroid cancer cells. Mechanistically, we found that down⁃regulation of CK2α expression inhibited YBX1 expression, thereby inhibiting the biological function of thyroid cancer cells. Conclusion CK2α promotes the development of thyroid cancer by promoting the expression of Y-box binding protein 1.