Mesenteric panniculitis is a non-neoplastic condition involving inflammation and fibrosis of the small bowel mesentery. We describe a man in his 60s who presented with 3 months of febrile episodes, confusion and weight loss. The diagnosis of mesenteric panniculitis had been established 2 weeks prior based on an abdominal computerized tomography scan. Extensive diagnostic investigations during his hospitalisation were unrevealing, and the symptoms were ultimately attributed to the mesenteric panniculitis. The fevers resolved over several weeks, and no further episodes have occurred since discharge. This case suggests that mesenteric panniculitis merits consideration in the differential diagnosis of fever of unknown origin.