It is well known that peripheral nerves are very vulnerable to electricity. However, only a small portion of individuals who have had high-voltage electrical injury exhibit peripheral nerve damage. The aim of this study was to investigate peripheral nerve damage in high-voltage electrical injury, which often occurs in the industrial field. The authors reviewed the medical records of patients who were admitted to their hospital from January 2009 to December 2011, because of electrical injuries. The results of nerve conduction studies (NCSs) were reviewed retrospectively. NCS data of the injured site were compared with those of the opposite noninjured site and follow-up data. Thirty-seven extremities were reviewed. The authors found that 18 of 33 median nerves (48.6%) showed abnormalities in at least one parameter and 15 of 36 ulnar nerves (41.7%) exhibited abnormalities. There was no evidence of demyelination. Eight patients had undergone NCS on the opposite normal extremities. The compound muscle action potential and nerve conduction velocity were higher at the normal site. Follow-up NCS were performed in 14 patients: the compound muscle action potential and nerve conduction velocity values of all patients were improved. High-voltage electricity damaged peripheral nerves by causing axonal injury rather than demyelinating injury. Hence, even if NCSs yield normal findings, peripheral nerves may be damaged. F/U studies and opposite examinations are required for the exact evaluation of peripheral nerve damage.