Arterial thrombosis associated with ulcerative colitis usually occurs in the postoperative period with a good response to anticoagulant therapy and embolectomy. Our patient was a 14-year-old girl with ulcerative colitis who presented with bilateral pulsless extremities, which did not respond to medical treatment and embolectomy. Subsequent colectomy did not save her limbs. The repeated thrombosis caused gangrene of extremities in the below knee region leading to bilateral amputation. Thrombosis can be the first presentation of ulcerative colitis.