A 48-year-old woman on maintenance hemodialysis was admitted with her left upper limb swollen and her left jugular vein dilated following the creation of an arteriovenous fistula on her left arm. The intracorporeal pressure during hemodialysis was found to be high. Venographic investigation showed severe stenosis of her left innominate vein accompanied by rich blood flow of the collaterals. Ligation of her fistula promptly reduced swelling of her left upper limb and dilatation of the left jugular vein. The exact cause of the stenosis could not be determined from venographic or computerized tomography findings. Idiopathic left innominate vein stenosis was diagnosed which we believe is the first case to be reported in a hemodialyzed patient.