In Japan, sacroiliitis is a very rare extraintestinal manifestation in patients with ulcerative colitis (UC), and it typically presents with intestinal symptoms. Radiography is used for diagnosis, and reveals erosions, sclerosis, and ankylosis, but magnetic resonance imaging is more useful for early detection. The treatment of spondyloarthropathy such as sacroiliitis and spondylitis includes physiotherapy, nonsteroidal anti-inflammatory drugs, sulfasalazine, and immunomodulators. In patients intolerant or cases refractory to these treatments, anti-tumor necrosis factor agents are recommended. Granulocyte and monocyte adsorption (GMA) apheresis was developed in Japan in the 1980s, and is currently used widely in clinical practice for UC patients. Unlike conventional medication, GMA apheresis has no serious adverse effects. We present the first report of a UC patient with sacroiliitis, who responded well to GMA therapy. GMA apheresis may be considered a new treatment option for UC-associated spondyloarthropathy that is refractory or tolerant to conventional treatment.