| Summary: | <i>Peucedanum franchetii</i> is a famous folk medicinal plant in China. However, the taxonomy of the <i>P. franchetii</i> has not been sufficiently resolved. Due to similar morphological features between <i>P. franchetii</i> and <i>Ligusticopsis</i> members, the World Flora Online (WFO) Plant List suggested that this species transformed into the genus <i>Ligusticopsis</i> and merged with <i>Ligusticopsis likiangensis</i>. However, both species are obviously diverse in leaf shape, bracts, and bracteoles. To check the taxonomic position of <i>P. franchetii</i>, we newly sequenced and assembled the plastome of <i>P. franchetii</i> and compared it with nine other plastomes of the genus <i>Ligusticopsis</i>. Ten plastomes were highly conserved and similar in gene order, codon bias, RNA editing sites, IR borders, and SSRs. Nevertheless, 10 mutation hotspot regions (<i>infA</i>, <i>rps8</i>, <i>matK</i>, <i>ndhF</i>, <i>rps15</i>, <i>psbA-trnH</i>, <i>rps2-rpoC2</i>, <i>psbA-trnK</i>, <i>ycf2-trnL</i>, and <i>ccsA-ndhD</i>) were still detected. In addition, both phylogenetic analyses based on plastome data and ITS sequences robustly supported that <i>P. franchetii</i> was not clustered with members of <i>Peucedanum</i> but nested in <i>Ligusticopsis. P. franchetii</i> was sister to <i>L</i>. <i>likiangensis</i> in the ITS topology but clustered with <i>L. capillacea</i> in the plastome tree. These findings implied that <i>P. franchetii</i> should be transferred to genus <i>Ligusticopsis</i> and not merged with <i>L</i>. <i>likiangensis</i>, but as an independent species, which was further verified by morphological evidences. Therefore, transferring <i>P. franchetii</i> under the genus <i>Ligusticopsis</i> as an independent species was reasonable, and a new combination was presented.
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