Postpoliomyelitis syndrome is a common neurological disorder that occurs in patients who have experienced paralytic poliomyelitis. Recently, as a result of vaccination against poliovirus, incidence of poliomyelitis is exceedingly low. However, many patients with postpolio syndrome may encounter anesthesia when undergoing surgery, such as for correction of foot deformity and other operations. We report on a 45-year-old woman who experienced paralysis of her contralateral limb after operation on the left foot under spinal anesthesia. Postoperative electromyography/nerve conduction study (EMG/NCS) was performed in order to determine the cause of paralysis. Motor power of the sequelae involved leg showed improvement with time and recovered fully to the preoperative level at six months after the index operation. A precise evaluation, including a physical examination and EMG/NCS, should be performed preoperatively when spinal anesthesia is planned for postpolio syndrome patients.