Ischiofemoral impingement (IFI) syndrome is an uncommon cause of gluteal and hip pain. We report on a case of a 20-year-old man who presented with chronic gluteal and hip pain with low back pain without a history of trauma or surgery. He was misdiagnosed with ankylosing spondylitis (AS) at another clinic. The patient was finally diagnosed with IFI syndrome according to pelvic magnetic resonance imaging findings at our hospital. After two weeks of medical and physical treatment, his pain showed gradual improvement. Because IFI syndrome is rarely reported in male patients, it might be misdiagnosed as AS. Therefore, IFI syndrome should be considered as a differential diagnosis of AS, particularly in young male patients with atypical pain characteristics.