Objective:To evaluate the prognostic factors of of medullary thyroid carcinoma (MTC), and explore the treatment measures on increasing survival rate.Methods :The records of 33 MTC patients treated at our hospital in past 14 years were retrospectively analyzed. The effects of clinical and pathological factors on the overall survival rate were evaluated by univariate and multivariate analyses.Results:The overall 5year survival rate was 63.03%. Based on univariate analysis,age,lymph node invasion,distant metastasis,tumor stage,and the extent of primary surgical resection were related with prognosis. In multivariate analysis,however,only age and the extent of the primary surgical resection were found to be statistically significant factors related to survival.Conclusions:The extent of the primary surgical resection and age are independent predictors of survival of patients with MTC. Vigilance of MTC in old patients with thyroid neoplasm and ensurance of radical tumor operation are the key points for increasing the overall survival of MTC.