Cancer stem cell (CSC) theory has drawn increasing attention in recent years. The presence of CSCs in thyroid cancer has been demonstrated by previous studies. Thyroid cancer CSCs are considered to be the potential culprit of occurrence, metastasis, recurrence and drug-resistance of thyroid cancer, thus, investigation in thyroid cancer CSCs may offer great significance for diagnosis, treatment and prevention of thyroid cancer. Here, the authors address the current knowledge about the thyroid cancer CSCs.