Abstract: OBJECTIVE To investigate the effect and mechanism of Jasminoidin on the directional differentiation of Nave T into Treg. METHODS CD4⁺CD62L⁺T was isolated from the spleen of mice by magnetic beads and induced to differentiate into Treg. Jasminoidin was used alone， and combined with ERK pathway blocker and JNK blocker. FCM was used to detect the proportion of Treg cells， and Western blot was used to detect the transcription factors of Foxp3， ERK， p-ERK，JNK and p-JNK. The expression of IL-10 were detected by ELISA method. RESULTS The percentage of Treg cells， the expression of Foxp3， p-ERK， p-JNK and the content of IL-10 in Jasminoidin group were significantly higher than those in control group when Jasminoidin was used on the basis of induction alone. On the basis of induction alone， ERK pathway blockers were added before Jasminoidin. The percentage of Treg cells， the expression of Foxp3 and the content of IL-10 were significantly lower than those of Jasminoidin group， but higher than those of control group. On the basis of induction alone， JNK blockers were added before Jasminoidin. The proportion of Treg cells， the expression of Foxp3， and the content of IL-10 were significantly lower than those of Jasminoidin group， but higher than those of control group. CONCLUSION Jasminoidin can promote the directional differentiation of Nave T into Treg and enhance its function， which may be associated with ERK and JNK.