Abstract： Objective To investigate the clinical features and prognostic factors of primary thyroid lymphoma. Methods Records of 44 patients with pathologically confirmed primary thyroid lymphoma were reviewed. Detailed clinical and laboratory data were included in univariate analysis, and statistically significant factors in univariate analysis were then included in multivariate analysis.Results In univariate analysis, Ann Arbor stage, performance status, IPI, number of extra-lymphatic site, B symptoms, Hb, LDH and β_2-MG level, therapy model, histology type and tumor mass were found to be the prognostic factors associated with overall survival in primary thyroid lymphoma. In multivariate analysis, performance status, IPI, LDH, β_2-MG level, histology type, and tumor mass were independent prognostic factors of overall survival. Conclusion Performance status, IPI, LDH and β_2-MG level, histology type and tumor mass were demonstrated as independent prognostic factors of the overall survival in primary thyroid lymphoma.