Abstract: Leber's hereditary optic neuropathy (LHON), a common blinding disease, is a maternally inherited degeneration of the optic nerve caused by point mutations of mitochondrial DNA. Complex I dysfunction, reactive oxygen species (ROS) overproduction, and cell apoptosis are the hypothesis of biochemical mechanism in LHON. Gene therapy is the ideal treatment for the disease. So far, the gene therapies used include allotropic expressing, transfecting with wild gene, and transfecting with antioxidant gene and so on. However, further investigation has to be done before clinical trials.