Primary thyroid lymphoma (PTL) comprises 5% of all thyroid malignancies. In this case series, we aim to review its clinical presentation, diagnosis, and treatment. We included five PTL patients. All were females (mean age of 59.8 years). All patients presented with a rapidly growing neck swelling, and only two had obstructive symptoms. All patients had solitary masses, aside from one patient who had two lesions. All were causing mass effect and two with invasion of the surrounding tissue. All were diagnosed with diffuse large B-cell lymphoma. Cytology examination for PTL demonstrates atypical lymphoid cells. Four patients in our series had chemotherapy and currently in remission. The fifth died early after the clinical presentation. Two had thyroid surgeries.