The larch hawk moth, Sphinx morio, belongs to the lepidopteran family Sphingidae that has long been studied as a family of model insects in a diverse field. In this study, we describe the complete mitochondrial genome (mitogenome) sequences of the species in terms of general genomic features and characteristic short repetitive sequences found in the A+T-rich region. The 15,299-bp long genome consisted of a typical set of genes (13 protein-coding genes, two rRNA genes and 22 tRNA genes) and one major non-coding A+T-rich region, with the typical arrangement found in Lepidoptera. The 316-bp long A+T-rich region located between srRNA and tRNAMet harbored the conserved sequence blocks that are typically found in lepidopteran insects. Additionally, the A+T-rich region of S. morio contained three characteristic repeat sequences that are rarely found in Lepidoptera: two identical 12-bp repeat, three identical 5-bp long tandem repeat, and six nearly identical 5~6 bp long repeat sequences.