A 48-year-old man presented with a fissured false aneurysms of the abdominal aorta due to Brucella suis. Clinical findings were lumbosciatic pain, fever, and sudation. Diagnosis was reached through abdominal computed tomographic (CT) scan and arteriograms. An extremely large false aneurysm, thrombosed and perforated posteriorly, was found in the infrarenal aorta. Semiurgent therapy consisted of resection of the aneurysm and prosthetic Dacron graft replacement associated with a transposed omental wrap. Antibiotic therapy was administered for three months. Although bacteriologic specimens were negative, brucellosis was diagnosed because of a positive Wright test and high Brucella antibodies in this patient originating from an endemic area. Six months after surgery he is apparently in good health.