The high-throughput sequencing method was used for the first time to determined complete mitochondrial genome of Orgyia postica. The complete mitochondrial genome was a circular molecule with 15,258 bp in full-length, including 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs) and 2 ribosomal RNA genes (rRNAs). The nucleotide composition of O. postica mitogenome was A: 37.6%, C: 7.9%, G: 14.8%, T: 39.7%. In addition, the results of the phylogenetic analysis indicate that O. postica had the closest relationship with Laelia suffusa. Our study will contribute to further research on the evolution of Lymantriidae and the identification of larva species.