Complete Chloroplast Genome Sequence and Phylogenetic Analysis of Paeonia ostii

, a common oil-tree peony, is important ornamentally and medicinally. However, there are few studies on the chloroplast genome of . We sequenced and analyzed the complete chloroplast genome of . The size of the chloroplast genome is 152,153 bp, including a large single-copy region (85,373 bp), a small single-copy region (17,054 bp), and a pair of inverted repeats regions (24,863 bp). The chloroplast genome encodes 111 genes, including 77 protein-coding genes, four ribosomal RNA genes, and 30 transfer RNA genes. The genome contains forward repeats (22), palindromic repeats (28), and tandem repeats (24). The presence of rich simple-sequence repeat loci in the genome provides opportunities for future population genetics work for breeding new varieties. A phylogenetic analysis showed that is more closely related to and than to and . The results of this study provide an assembly of the whole chloroplast genome of , which may be useful for future breeding and further biological discoveries. It will provide a theoretical basis for the improvement of peony yield and the determination of phylogenetic status.