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Mitochondrial genome sequences have been used in diverse fields of biology. In this study, we sequenced the complete mitochondrial genomes (mitogenome) of two pear pests: <i>Cacopsylla jukyungi</i>, the most damaging insect pest to commercial pears in South Korea, and <i>Cacopsylla burckhardti</i> (Hemiptera: Psyllidae). The two mitogenomes were compared to confamilial species to accumulate genetic information and understand evolutionary characteristics of the family Psyllidae. The 15,438 bp-and 14,799 bp-long complete mitogenomes of <i>C. jukyungi</i> and <i>C. burckhardti,</i> respectively, had many features typical of insect mitogenomes; however, at 1283 bp, the <i>C. jukyungi</i> mitogenome had an unusually long A+T-rich region, which was composed of two identical 540-bp repeat sequences. Among the intergenic spacer regions, the one located at the <i>ND1</i> and <i>trnS₂</i> junction was relatively well conserved in length (mostly within 23–36 bp). This region had a high sequence identity in all Psyllidae, possessing a 5-bp consensus sequence (CGGTA), which is speculated to have a functional role. Though the A+T-rich region in available Psyllidae mitogenomes varied substantially in length (662–1430 bp) and sequence divergence, all species had a conserved sequence stretch at the 3′-end of <i>srRNA</i>, which is also speculated to have a functional role. Genetic divergence among genes indicated the lowest variability in <i>srRNA</i>, <i>lrRNA</i>, and <i>COI</i>, whereas <i>ATP8</i> and <i>ND6</i> showed the highest variability at both family and genus (<i>Cacopsylla</i>) levels. Our data provide evidence that the family Psyllidae, including current <i>C. jukyungi</i> and <i>C. burckhardti</i>, have evolutionary unique features that were previously undetected, along with the unique A+T-rich region structure in <i>C. jukyungi</i>.