A 36-year-old woman was admitted to our hospital due to swelling and redness of the left lateral malleolus and dorsum of the left foot with severe pain, with a flare-up of ulcerative colitis (UC). A pathologic examination by skin biopsy led to a diagnosis of pyoderma gangrenosum (PG). She was treated with the intravenous administration of prednisolone (60 mg/day), and granulocyte and monocyte adsorption apheresis (GMA) was performed twice-a-week for 5 weeks. This treatment dramatically improved both the skin and colonic mucosal lesions. These results suggest that a combination of GMA and corticosteroids might be recommendable to induce the remission of serious PG complicated with UC.