Abstract: OBJECTIVE To explore the correlation between the expression of triterpenoids and biosynthetic enzyme genes in Alisma orientale under temperature stress. METHODS Alisma orientale under different temperature(0, 6, 16, 26℃) cultivations were used as test materials, the content of eight triterpenoids in leaves, including alisol A, alisol B, alisol F, alisol G, alisol A 24 acetate, alisol B 23 acetate, alisol C 23 acetate and alisol F 24 acetate, was detected by UPLC-MS/MS. And then the qRT-PCR was utilized to analyze the expression of biosynthetic enzyme genes HMGR, SQS, FPPS and MVD mRNA in triterpenoid synthesis pathway. RESULTS Alisol B 23 acetate and the total content of eight triterpenoids in leaves of Alisma orientale were positively correlated with the relative expression of SQS and HMGR mRNA, respectively(P<0.05). While, there was no significant difference in the expression of genes FPPS and MVD mRNA with different temperature interventions. CONCLUSION SQS and HMGR may be the rate-limiting enzymes in the synthesis of triterpenoids in Alisma orientale, and their expression is regulated by temperature.