OBJECTIVE：To study the improvem ent effects of total flavonoids from Morus alba on glycolipid metabolism ， inflammation and oxidative stress in gestational diabetes mellitus （GDM）model rats ，and to investigate the potential mechanism. METHODS：After feeding high fat diet for 8 weeks，female SD rats with FBG ＜6.67 mmol/L were caged with male SD rats . Pregnant female rats were randomly divided into control group ，GDM group ，M. alba total flavonoids low-dose ，medium-dose and high-dose groups （50，100，200 mg/kg），with 10 rats in each group. Except for control group ，other groups were given intraperitoneal injection of streptozotocin 25 mg/kg once to induce GDM model. After injection ，rats in each administration group were given corresponding drugs intragastrically ，control group and GDM group were given normal saline 10 mL/kg intragastrically ， once a day ，for consecutive 18 days. The levels of FBG were determined on the 3rd，7th and 18th day of pregnancy （G3d，G7d and G18 d）；the levels of blood lipids （TG，TC，LDL-C，HDL-C）and inflammatory factors （TNF-α，IL -6，IL-8），oxidative stress indicators（MDA，SOD，GSH，CAT）in serum were determined on G 18d. The protein and mRNA expressions of PPARγ and NF-κB， the expression of AMPK mRNA and p-AMPK protein were measured by Real-time-PCR and Western blotting. RESULTS ： Compared with control group ，the levels of FBG （G3d，G7d，G18d），TG，TC，LDL-C，TNF-α，IL-6，IL-8 and MDA ，protein and mRNA expression of NF-κB in GDM group were significantly increased，while the levels of SOD ，GSH and CAT ，the expressions of PPARγ protein and mRNA，AMPK mRNA and p-AMPK fcksjf@126.com protein were significantly decreased （P＜0.01）. Compared with GDM group ，the levels of FBG （G3 d，G7 d，G18 d），TG， huawei99@163.com TC，LDL-C in M. alba total flavonoids medium-dose and high- dose groups and the levels of TNF-α，IL-6，IL-8 and MDA ，protein and mRNA expression of NF-κB in M. alba total flavonoids groups were significantly decreased ；the levels of SOD ，GSH and CAT ，the expressions of PPARγ protein and mRNA， AMPK mRNA and p-AMPK protein were significantly increased （P＜0.05 or P＜0.01）. CONCLUSIONS ：Total flavonoids from M. alba can improve the glycolipid metablism ，inflammation and oxidative stress in GDM model rats ，the mechanism of which may be related to the activation of PPARγ pathway.