An siRNA for specifically targeting a PMP22 mutant gene and a pharmaceutical composition for preventing or treating Charcot Marie Tooth disease, which includes the same, are provided. According to the present invention, it is confirmed that selective suppression of a PMP22 mutant allele by a non-viral delivery system of siRNA may improve demyelinating neuropathic symptoms of CMT in vivo, enhance a motor ability and increase a volume of muscle. Therefore, the siRNA may be used in a useful method for treating various dominantly inherited peripheral neuropathies including CMT.