We report the case of a 75-year-old man who presented for evaluation of painless hematuria persisting for more than 1 month. At the time of presentation, the patient did not report any systemic symptoms and had no fever, weight loss, or dysuria. Computed tomography showed several enhancing, sessile polyps in the gall bladder (1.5 cm or smaller). There was no associated stone or biliary dilation. Since no other abnormality was evident, we performed laparoscopic cholecystectomy. He was diagnosed as having B-cell lymphoblastic lymphoma (B-LBL) after surgical resection of the gall bladder (GB). As the left mandibular swelling was developed after the diagnosis of the B-LBL involving GB, facial magnetic resonance imaging (MRI) was added to the imaging scan. Facial MRI revealed mass formation in the left mandible, left medial pterygoid, masticator, and buccinator muscles. The biopsy samples from the mandibular bone were also diagnosed as B-LBL. The definitive pathological diagnosis was B-LBL, stage IV. Systemic chemotherapy was done with subsequent response in size of the left mandible mass.