To investigate codon usage bias of Persicaria odorata， we sequenced the chloroplast genome of P. odorata using the Next-Generation Sequencing. The raw sequencing data were quality control filtered， assembled， annotated and constructed a physical map. Furthermore， we systematically analyzed the codon usage bias of 52 protein-coding sequences. Our comprehensive analysis shows that the chloroplast genome was 159 897 bp in length， with a typical quadripartite structure consisting of a large single-copy region （LSC）， a small single-copy region （SSC）， and two inverted repeat regions （IR）. The overall GC content of codons in the P. odorata chloroplast genome was 38.88%， with GC1>GC2>GC3， showing a preference for codons ending with A/U. The effective number of codons （ENC）， the codon adaptation index （CAI）， the codon bias index （CBI） and the frequency of optimal codons （Fop） ranged from 36.29 to 54.14， 0.10 to 0.30， -0.26 to 0.19， and 0.26 to 0.53， respectively. These analysis collectively indicated weak codon usage bias in the chloroplast genome of P. odorata. Neutrality plot analysis， ENC-plot analysis， and PR2-plot analysis revealed that codon usage bias in the P. odorata chloroplast genome resulted from both mutation pressure and selection pressure and was primarily determined by the selection pressure. A total of 10 optimal codons were identified. Our study established a fundamental framework for functional genomics and molecular breeding of P. odorata by providing：（i） theoretical foundations and molecular marker resources for further functional analysis of chloroplast genes， （ii） evolutionary studies， and （iii） molecular breeding within Polygonaceae.

Persicaria odorata  /  Chloroplast genome  /  Codon usage bias  /  Optimal codon