Primary thyroid lymphoma (PTL) is a rare condition, posing significant diagnostic challenges due to limited incidence and data. However timely and accurate diagnosis is crucial for effective management. This study aims to analyze the clinicopathological features of PTL cases observed over 15 years at a tertiary national referral hospital. PTL cases from 2009 to 2023 at Universitas Indonesia - Dr. Cipto Mangunkusumo Hospital archives were retrospectively analyzed, with an assessment of clinical data, histopathological, and immunohistochemistry analysis. Statistical analysis was conducted using Chi-Square and Kruskal Wallis. Women constituted the majority of cases (male-to-female ratio was 1: 2.6), with a median patient age of 55 years. Of the 40 identified PTL cases, only one was a T-cell lymphoma among the non-Hodgkin lymphomas (NHL). The NHL subtypes included diffuse large B-cell lymphoma (DLBCL [72.5 %]), marginal zone lymphoma (15.0 %), and follicular lymphoma (FL [10.0 %]). An enlarged neck mass (94.7 %) was the most frequent symptom, and 42.1 % had a history of Hashimoto's thyroiditis. The overall surviving proportion in the present study is 80.7 %, with the median survival duration of 14.5 months, ranging from 1 to 54 months. The longest duration of survival documented in FL case and the shortest in DLBCL case. Lymphoepithelial lesions could be found in all lymphoma types. The main diagnostic and treatment modality used was surgery. Prompt diagnosis and personalized treatment approaches are important to improve survival outcomes. PTL should be anticipated in middle-aged women with rapid enlarged neck mass and a history of Hashimoto's thyroiditis.