To explore the chemical composition and content characteristics of the branch bark of different Eucommia clones under the short-period foliar forest model and provide a basis for the quality control and rational utilization of the branch bark of E. ulmoides for foliar forests.The main active components and volatile components of the branches bark of 8 E. ulmoides clones were determined by high-performance liquid chromatography,headspace solid-phase microextraction,and gas chromatography-mass spectrometry,and their fingerprints were studied by Fourier transform infrared spectrometer.The results showed that the iridoids such as aucubin,geniposidic acid,and genocide were higher in E. ulmoides branch bark,and the content of each active component was significantly different among the eight clones.Seventy volatile substances in 7 categories of esters,alcohols,aldehydes,terpenes,ketones,lactones,and alkenes were isolated and identified from the branch bark of 8 E. ulmoides clones.Among them,alcohols,aldehydes,and esters were the main volatile constituents of E. ulmoides branch bark.The relative contents of terpenoid isophotal in clones EU2,EU5,and EU8 were the highest,accounting for 7.24%,9.40%,and 6.35%,respectively.Principal component analysis showed that the main active components contributing to the clones EU1,EU4,and EU5 on PC1 were iridoids.Eight clones of E. ulmoides were divided into three groups,of which group I included clones EU1,EU4,EU5,group II included EU3,EU4,and group III had EU2,EU6,and EU8.PLS-DA screened Twenty-two differentially volatile components.Substance components are mainly ester volatile components.EU1,EU4,and EU5 clones have infrared solid absorption peaks at 1 053 cm^-1.This study provides a reference for the future development and utilization of E. ulmoides leaf forests.