Primary sarcoma of the gallbladder is a very rare neoplasm, and there are few instances of its diagnostic and therapeutic management. We describe a 66-year-old male patient with a sarcoma of the gallbladder. He initially underwent a laparoscopic cholecystectomy, converted to an open procedure. Histology showed a primary sarcoma of the gallbladder (NOS). A relaparotomy, with resection of the cystic stump, anatomical hepatic resection of the fifth segment, including the bed of gallbladder, and lymphadenectomy was performed a few days later. The two surgical interventions were done with no major complications, and a radical resection status was achieved. Histological investigation revealed a malignant mesenchymal tumor lesion, which was classified as a myogenous sarcoma with a hemangiopericytomatous pattern. After an 11-month, uneventful, postoperative course, local tumor recurrence was diagnosed. Palliative chemotherapy was scheduled, but the patient died of advanced tumor recurrence 10 days after this diagnosis. Despite a poor overall prognosis, extensive surgical resection is favored for myogeneous sarcoma of the gallbladder; this procedure is based on precise clarification of the histopathological diagnosis, and can be followed by attempts with radiation of chemotherapy if early diagnosis-finding has failed. This approach allowed, in our patient with this rare neoplasm, a remarkable tumor-free survival of almost 1 year.