Abstract: There are about 60 species of Lagerstroemia in the world, and more than 500 species have been cultivated.Lagerstroemia species is an excellent garden ornamental plant. In addition to bright color and the characteristics of air purification, it has important value in garden and horticultural applications. At present, due to the frequent interspecific hybridization and gene introgression, the morphological classification system can not satisfy the genetic diversity study of Lagerstroemia. With the development of modern biotechnology, studies based on chloroplast genome have shown obvious advantages in the study of species relationship. DNA fragments and simple repeat sequences extracted from chloroplast genomes are often used as molecular markers for identification and classification of plants. So far, the chloroplast genomes of 22 species of Lagerstroemia have been sequenced. The phylogenetic relationships of 22 species of Lagerstroemia have been analyzed by Bayes' method, and 22 species of Lagerstroemia are monophyletic groups. It is concluded that the chloroplast genome size is about 150 kbp, the largest is L. venusta with a length of 152 521 bp, and the smallest was L. guilinensis with a length of 151 968 bp. The length of LSC region is 83-84 kbp, the length of SSC region is 16 kbp, the length of IR region is 25 kbp, and the content of GC in chloroplast genome is 37.6%-37.7%. The research reviews the structure of chloroplast genome of Lagerstroemia and its application in DNA barcoding, SSR and phylogeny in order to understand the research status of the chloroplast genomes of Lagerstroemia and improve the evaluation and understanding of the application of Lagerstroemia in landscape architecture. It will lay a foundation for further research on germplasm resources identification, genetics and phylogeny of Lagerstroemia based on chloroplast genome and provide data support for breeding more Lagerstroemia plants used in garden sightseeing.