The authors report the case of a woman aged 67 years who presented an acute ischemia of the lower limbs. A surgical exploration showed no atherosclerosis or thrombus. A biopsy of the femoral artery found an extensive mononuclear cell infiltration of the media and a fragmentation of internal elastic lamina. The diagnosis of Horton disease was considered and confirmed by the presence of clinical signs of polymyalgia rheumatica and inflammatory syndrome (erythrocyte sedimentation rate: 75 mm). Corticosteroid therapy was started with success. A year after discharge there was no recurrence of ischemic manifestations and the erythrocyte sedimentation rate was normal. Involvement of lower limbs in Horton disease is rare and exceptionally proven. But postmortem studies indicate that it is more frequent than previously reported. The diagnosis should be considered in the differential diagnosis of any unexplained case of peripheral vascular disease occurring in the middle-aged or elderly.