Leber's hereditary optic neuropathy (LHON) is caused by a point mutation in the mitochondrial deoxynucleic acid (mtDNA) and accounts for 30+ of bilateral optic atrophy of unknown etiology. The authors found a Korean family with mtDNA mutations in the nucleotide positions (np) 11778 and np 4216. This is the first report confirming a secondary mtDNA np 4216 mutation in Koreans, as well as the first report of a Korean family harboring both primary and the secondary mutations that the authors are aware of.