Background/aim: Primary thyroid lymphoma (PTL) is a very rare thyroid malignancy. It should be diagnosed and treated immediately and accurately. Our aim was to evaluate the diagnostic methods and treatment results for patients with PTL.Materials and methods: We retrospectively evaluated the records of 11 patients with PTL from 2009 to 2015, diagnosed at our institute. Age, sex, stage, histopathologic type, presence of Hashimoto's thyroiditis, diagnostic methods, treatment types, and recurrence were examined.Results: Six patients were female, 5 were male, and the median age of the patients was 61 years (range: 15-76 years). All patients had a large palpable mass in the neck. Fine needle aspirate (FNA) biopsy was performed in all patients; however, it was useful only in the diagnosis of 7 patients. Excisional and surgical biopsy was performed in 4 patients. All patients had non-Hodgkin B-cell lymphoma, including 9 cases of diffuse large B-cell lymphoma (DLBCL), and 2 patients had mucosa-associated lymphoid tissue (MALT) lymphoma. Recurrence was observed in one patient. Median survival was 34 months.Conclusions: The preferred option for the diagnosis of PTL should be FNA biopsy, and the treatment should be decided on according to whether the disease is limited to the thyroid gland or not, its histological type, and its stage.