Takayasu arteritis (TA) is a chronic inflammatory disease that involves the aorta and its major branches. Since overproduction of interleukin-6 (IL-6) seems to play a pathogenic role in TA, we used the anti-IL-6 receptor (IL-6R) antibody tocilizumab to treat a 20-year-old woman with refractory active TA complicated by ulcerative colitis (UC). Treatment with tocilizumab improved the clinical manifestations of TA and the abnormal laboratory findings in this patient and ameliorated the activity of UC. These results indicate that IL-6R inhibition with tocilizumab might be a future treatment option for TA.