Objective To investigate the association between preoperative serum TSH concentration and thyroid carcinoma in patients with nodular goiter.Methods Data of 632 patients with nodular goiter from January 2004 to December 2010 were analyzed retrospectively.Results Preoperative serum TSH in nodular goiter with thyroid carcinoma was higher than that without thyroid carcinoma，which was （2.10±1.38）mU/L and （1.51±0.98）mU/L，respectively （P＜0.000 1）.The risk of malignancy increased as serum level of TSH rose in nodular goiter patients （P=0.023 5），the ratios were 9.91% （0.3-0.9mU/L），12.37% （0.9-1.7mU/L）， 20.09% （1.7-4.8mU/L），and 27.27%（＞4.8mU/L）.The TSH level of stageⅢ-Ⅳ patients higher than that stageⅠ-Ⅱ patients （P=0.030 6）.The diameter of tumor ＞4 cm had highest mean TSH level， and which ≤ 2cm had lowest mean TSH level（P=0.018 6）. Conclusion Preoperative serum TSH level perhaps is a risk predictor for nodular goiter with thyroid carcinoma.