Objective To study the relations between the expression of estrogen receptor (ER), progesterone receptor (PR) and tumor infiltration and metastasis in thyroid carcinoma. Methods By using immunohistochemical staining (SABC method), the expressions of ER and PR in 100 cases of thyroid carcinomas and 28 cases of benign thyroid lesions were studied. Results The positive rate of ER and PR expressions were 67.0% and 62.0% respectively in thyroid carcinomas, they had correlation with cell differentiation and type of histology but positive expressions did not relate to age and sex. The positive rate of ER and PR in the non-metastasized group was 75.4% and 70.5%, significantly higher than that of the metastasized group in which were 53.8% and 48.7% (Ｐ＜0.05). Conclusion The results suggest that the expressions of ER and PR are related to tumor differentiation and may indicate a poor prognosis.