Osteomyelitis of the pubic symphysis is not common and has often been reported to occur after urological or gynecological procedures. It can be spontaneous in origin but it also is associated with trauma, athletic exertion, pregnancy, and parturition. The early symptoms of osteomyelitis of the pubic symphysis mimic those of osteitis pubis, and therefore, the differential diagnosis between these two entities is of clinical importance. A fifty nine-year-old man who had previously received debridement and wide excision of perianal necrotizing fasciitis visited our hospital with pain on both inguinal areas. The core biopsy of the pubic symphysis and aspiration culture were performed, from which Pseudomonas aeruginosa was recovered. He was treated with parenteral ceftazidime for 5 days followed by cefepime for 7 weeks and showed favorable clinical response. To our knowledge, this is the first report on osteomyelitis of pubic symphysis resulting from debridement and wide excision of perianal necrotizing fasciitis in Korea.