Abstract: Cinnamomum plants are rich in terpenoids such as camphor, D-borneol, linalool, etc.These terpenoids are widely used in medicine, cosmetics, food, etc., and have important medicinal and economic values.Terpene synthase (TPS) in Cinnamomum plants, as a critical enzyme for synthesizing terpene products, has received more and more attention and research from researchers in recent years.In this study, we collected and analyzed the transcriptome data of Cinnamomum camphora, Cinnamomum chago, Cinnamomum kanehirae, Cinnamomum parthenoxylon, Cinnamomum tenuipile, Cinnamomum verum, Cinnamomum burmannii, Laurus nobilis, Lindera glauca and Litsea cubeba using bioinformatical methods, and a total of 165 TPS genes were mined, which encoded proteins with nine conserved sequence motifs such as RR(X)8W, RLG, FRLLR, RWD, EA(X)W, RDR, DDXXD, DXDD, and NSE/DTE.Phylogenetic anal. classified the TPSs of Cinnamomum plants into five subfamilies (TPS-a, TPS-b, TPS-c, TPS-e/f and TPS-g).The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway anal. revealed their involvement in isoprene, mono-, sesqui-, and diterpene biosynthesis.Three-dimensional structure predictions revealed their modular structural organization.Mol. docking investigations further elucidated the interaction of conserved motifs and metal ions or substrates.Class I TPS catalytic activity was associated with NSE/DTE and DDXXD motif interactions with metal ions, while Class II TPS functionality emerged from DXDD motif binding with geranylgeranyl diphosphate (GGPP).Tissue-specific and chemotype-dependent expression patterns were observed across the TPS genes, which suggested spatial and metabolic specialization in terpenoid biosynthesis.This comprehensive investigation advances our understanding of terpenoid synthesis in Cinnamomum plants, lays a theor. foundation for analyzing the regulatory mechanism of terpenoid biosynthesis, and provides a theor. basis for the genetic improvement and further utilization of Cinnamomum plants.