Ulcerative colitis (UC) associated with Takayasu's disease (TD) is not common in Japan. Here, we report two patients with both diseases who received a total proctocolectomy. Patient 1, a 41-year-old woman with chronic continuous type UC, was first diagnosed with TD at the age of 10 years. Subsequently, she was diagnosed with UC and rectal cancer. HLA typing showed A2, A31(19), B52(5), and DR2(DRB1*1502). Coronary angiography showed 90% narrowing of the right coronary artery (RCA). After alleviating the RCA narrowing by percutaneous transluminal coronary angioplasty (PTCA), we performed a total proctocolectomy and ileostomy. Patient 2, a 20-year-old woman, was first diagnosed with TD at the age of 13 years. Severe symptoms, indicating fulminant UC, started 1 month prior to hospitalization. She was judged as needing surgery because the symptoms were not alleviated even with high doses of prednisolone. HLA typing showed A2, A31(19), B52, B61(40), DR2(DRB1*1502), and DR4 (DRB1*0405). Aortography showed a narrowing of the right renal artery; however, her renal function was normal. Based on these findings, we performed a three-stage operation for total proctocolectomy. Previously, we have reported that the DRB1*1502 and DRw11 genes were closely related to the intractability of UC. To date, we have not determined whether or how the DRB1*1502 gene might be related to TD. As the number of cases of UC associated with TD increases, it will be necessary to examine their DR2 subtypes.