Based on the tea plant transcriptome database, we cloned two fulllength cDNAs of the isopentenyl diphosphate isomerases (CsIDI1 and CsIDI2) using RTPCR method from the tea plant cultivar of Tieguanyin. CsIDI1 was 1 378 bp in length and contained a 894 bp ORF encoding 297 amino acids, which shared 95% similarity with Vitis vinifera IDI. Subcellular localization prediction showed that CsIDI1 was localized to the chloroplast. Additionally,the length of CsIDI2 was 1 216 bp and contained a 717 bp ORF encoding 238 amino acids, CsIDI2 had similarity with 96% homologous to Sesamum indicum IDI and predicted to was located on the cytoplasm. Both CsIDI1 and CsIDI2 contained a typical NUDIX hydrolase domain. The results of realtime quantitative PCR showed that CsIDI1 and CsIDI2 were expressed in different tissues of tea plant，wherease the expression of CsIDI2 was relatively higher, The expression of CsIDI1 and CsIDI2 was significantly higher in female parent Huangdan and high scent hybrids than that in male parent Tieguanyin, showing the heterosis of aroma. During the greenmaking procedure of Oolong tea , the expression level of CsIDI2 was significantly higher than that of CsIDI, indicating that CsIDIs play an important role in the formation of tea terpenoids aroma.