Two patients with Takayasu arteritis are reported who presented with fever of unknown origin. Takayasu arteritis was diagnosed at the prepulseless period after stenotic lesions of the aorta, and its branches were seen with imaging methods. In the first month of steroid treatment, hypertension developed in both patients that was related to fibrosis in stenotic lesions in renal arteries. Both patients were treated with percutaneous transfemoral renal angioplasty. Takayasu arteritis should be considered in the differential diagnosis of fever of unknown origin, especially in young women. Absence of the physical findings related to vasculitic lesions will not rule out the disease, which can be seen in the prepulseless period.