Fine needle aspiration (FNA) was used to make a definitive diagnosis of osteomyelitis of the pubis with negligible trauma to an elderly patient. The material obtained was adequate to resolve the differential diagnosis of osteomyelitis versus osteitis pubis occurring after urologic surgery. The three basic components of acute bacterial osteomyelitis, an acute inflammatory cell exudate of neutrophils, necrotic bone and bacteria in cells, were present in the FNA smears and cell blocks; the presence of bacteria was shown by Gram staining of FNA smears and culture of part of the FNA specimen.