Temporal arteritis is a clinical manifestation of giant cell arteritis. The etiology of this disease is still unknown. Sudden onset and wide variations of incidence are reported in different parts of the world. Acute onset is often associated with flu-like symptoms, indicating that infectious factors probably act as precipitating agents. We describe a 72-year-old man referred to our department in January 1999 for unremitting fever and temporal arteritis associated with Chlamydia pneumoniae infection.