Rotunda rotundapex (Miyata & Kishida, 1990) is a silk moth identified in Korea. We completed its mitochondrial genome which is 15,298 bp long and the shortest mitogenome of Bombycidae s.str. It includes 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNAs, and a control region. Comparison with COI sequence of Taiwan isolate suggests the Korean population of this species can be a novel species. Gene order of R. rotundapex mitogenome is conserved as in other Bombycidae species. Phylogenetic trees show that R. rotundapex is closely related to genus Rondotia