The Chinese scorpion, Mesobuthus martensii (Karsch, 1879), is a medically important arthropod, with its venom representing a rich resource for bioactive molecules. Very little is known about the natural enemies of scorpion, albeit some populations are on the verge of extinction due to human over-exploitation. In this study, we found, for the first time, that a medically and forensically important flesh fly, Sarcophaga dux (Thompson, 1869), can parasitize M. martensii in China.We identified the flesh flies by both morphology and DNA-based methods employing the mitochondrial cytochrome C oxidase I gene. Our phylogenetic analyses indicated that S. dux was not monophyletic with respect to Sarcophaga aegyptica (Salem, 1935) and Sarcophaga harpax (Pandellé , 1896), and was comprised of two distinct mitochondrial lineages. The flesh flies infesting the Chinese scorpion formed one of the paraphyletic lineages of S. dux. These lineages together with S. aegyptica and S. harpax represented a species complex with genetic distances ranging from 1.0 to 1.5%. Our findings suggested that S. dux was capable of larviposition nocturnally.