목적: Primary thyroid lymphoma (PTL) is rare pathology of the thyroid gland, with generally good prognosis. Proper evaluation of fine needle aspiration cytology specimens is essential in diagnosis as they may be confused with Hashimoto's thyroiditis or anaplastic thyroid carcinomas(ATC). The aim of this study was to analyze the clinical patterns treatment outcomes in patients with PTL. 방법:Medical records of 28 patients with thyroid lymphoma treated between February 2000 and July 2014 were retrospectively reviewed. 결과:Of 28 patients, 22 (78.6%) patients were female and eight (21.4%) patients male. The median age at diagnosis was 65.5 (range,42-82) years. Common clinical feature of PTL is rapidly growing mass-like ATC. Of 28 patients, six was diagnosed as ATC. Four patients was diagnosed as papillary thyroid cancer by preoperative FNAC, however, finally proven PTL. There were 6 (21.4%) patients with mucosa-associated lymphoid tissue (MALT) lymphoma and 22 (78.6%) patients had high-grade lymphoma. The median follow-up was 55.8 (range, 2152) months. Seventeen (60.1%) patients had hypothyroidism were already diagnosed Hashimotos thyroiditis. Patients were treated with surgery (n=6), chemotherapy (n=9) alone, or a combination of these methods (n=13). Four (14.3%) patients experienced recurrence with pathology of diffuse large B cell lymphoma. There was no death or relapse among MALT lymphoma patients. Five-year overall survival (OS) and 5-year progression-free survival (PFS) were 82.3% and 75.9%, 결론:Patients with PTL showed a favorable treatment outcome, especially with MALT lymphoma. More reliable and specific finding for differentiating PTL from other type of aggressive thyroid cancer such as ATC should be investigated.