A 60-year-old woman (case 1) experienced severe pain in the lower part of her leg and sciatic nerve paralysis the following day after intra-arterial infusion of cisplatin for the treatment of uterine body cancer. The symptoms gradually improved in the next six months. The lesion was not detected on pelvic MRI after two months. A 49-year-old woman (case 2) complained of severe pain in the lower part of her leg three days after intra-arterial infusion of cisplatin for the treatment of uterocervical cancer. Enhancement of the right first sacral root was demonstrated by the pelvic MRI. The symptoms gradually improved with the symptomatic therapy. To our knowledge, this is the first report of lumbo-sacral radiculopathy associated with intra-arterial infusion of cisplatin presenting the enhanced lesion in the root on MRI. It was suggested that lumbo-sacral radiculopathy induced by intra-arterial infusion of cisplatin is not a rare complication and that MRI is useful in confirming the diagnosis. Various precautions should be undertaken to prevent such complications.