In order to further explore the genes related to terpenoid synthesis in the transcriptome of Narcissus tazetta var. chinensis, and to understand the metabolic pathways and molecular regulation mechanisms of N. tazetta, the study used the N. tazetta ‘Yunxiang’ as the material, screened the annotated terpenoid synthesis pathway genes and reannotated them with NCBI blastn based on the sequencing of the petal and corolla transcripts at the flowering stage. The representative gene was further screened by the expression of some candidate genes and the biosignal analysis. The isopentenyl pyrophosphate isomerase gene NaIDI was cloned by RTPCR, and analyzed for its protein sequence and specific expression. The results showed： (1) blast alignment screened 52 Unigenes associated with the upstream pathway of terpenoid synthesis, and secondary screening obtained 11 significant differentially expressed genes. (2) The open reading frame (ORF) of NaIDI gene is 858 bp in length and encodes 285 amino acids. The amino acid sequence was 97.19% similar to that of N. tazetta ‘Jinzhanyintai’. The subcellular localization is predicted in chloroplast. The phylogenetic analysis shows that it was closely related to asparagus. (3) The results of realtime fluorescence quantitative analysis showed that NaIDI was significantly expressed in different flowering periods and different tissues and organs of N. tazetta, and it had the highest expression in the corolla during the flowering stage, and it was consistent with the regularity of volatile steroids in different periods of flowering and different tissues and organs，indicating that NaIDI plays a certain role in the metabolism of terpenes.