A 51-year-old otherwise healthy woman was referred to our hospital with a fever of unknown origin, liver dysfunction, and anemia. One month prior, she had persistent and spontaneous anterior neck pain, with no exacerbation during swallowing or neck movements. Physical examination revealed no pharyngeal or tonsillar abnormalities, heart murmur, arthritis, skin rash, or lymphadenopathy, except for mild bilateral common carotid artery tenderness at the level of the thyroid cartilage. Blood tests showed nonspecific chronic inflammatory findings, anemia, and liver damage, whereas blood cultures, viral antibodies, interferon-γ release assay, and antibodies specific for any collagen disease showed negative results. Echocardiography and computed tomography without contrast of the neck, chest, abdomen, and pelvis showed no apparent abnormalities. She was subsequently diagnosed with Takayasu arteritis using positron emission tomography. Identifying a characteristic history of bilateral carotid artery tenderness and subsequent positron emission tomography can be useful for diagnosing Takayasu arteritis.