The number of reported mitochondrial genomes (mitogenomes) from the monotypic Lasiocampoidea has been limited until recently. In this study, we sequenced the complete mitogenome of the lappet moth, Kunugia undans (Lepidoptera: Lasiocampidae), and compared it to those of other lasiocampid species and macroheteroceran superfamilies (59 species in six superfamilies). The 15,570-bp long K. undans genome had the typical set of genes found in animal mitogenomes, with the exception of one additional trnR that are located between trnA and trnN loci. Considering that the two trnR copies are located in tandem with proper secondary structures and identical anticodons, a gene duplication event might be responsible for the presence of the two tRNAs. In summary, the general mitogenome characteristics of Lasiocampoidea did not differ greatly from the remaining macroheteroceran superfamilies, but it did exhibit some unique features.