Primary non-Hodgkin lymphoma (NHL) of the gallbladder (GB-NHL) is exceedingly rare. We present our experience on a 78-year-old male with chief complaints of fever, chills, and epigastric dull pain. Abdominal computed tomography (CT) scan showed a few stones and focally thickened gallbladder wall. He received cholecystectomy under the preoperative diagnosis of acute cholecystitis with septic shock, while pathologic examination revealed cholelithiasis and diffuse large B-cell lymphoma without acute inflammation. Staging procedures revealed a stage IE tumour and the patient received adjuvant radiotherapy. Relapse as a large retroperitoneal mass was noted 32 months later and he passed away three years after initial diagnosis. A literature review revealed 20 cases of GB-NHL. We find that, including our current case, the median age is 63 years and 8 of 19 (42%) tumours are associated with gallstones. The mean and median survival of 15 patients with complete follow-up information is 75 and 36 months, respectively. Mucosa-associated lymphoid tissue (MALT) lymphoma seems to carry a longer survival than non-MALT lymphomas.