【Abstract】Objective To observe the effect of astragaloside IV (AST) on oxidative stress of uterus in female rats with hypothyroidism. Methods A total of 60 female rats [4 weeks old, weighing (110±10) g] were randomly divided into control group, model group, AST treatment groups (20,40 and 80 mg/kg) and positive drug group (levothyroxine sodium, 9×10-3 mg/kg). The rat model of thyroid dysfunction was induced with intragastric infusion of 0.1% propylthiouracil at a dose of 10 ml/kg. Then the serum contents of related indicators were detected with corresponding test kits, including myeloperoxidase (MPO), catalase (CAT) and nitric oxide (NO). The activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), the contents of malondialdehyde (MDA), lactate dehydrogenase (LDH) and Ca²⁺ in the uterine tissues were measured with corresponding test kits, and the level of high energy phosphates (HEP) was detected with high performance liquid chromatography. The contraction tension (CT) and contraction frequency (CF) of the smooth muscle samples derived from isolated uterine were measured, and uterine motility (UM) was calculated. Statistical analysis were performed by SPSS statistics 17.0. ANOVA was used for comparison among groups, and adjusted SNK test was used for comparison between two groups. Results MPO activity and NO level were decreased significantly, and CAT activity was enhanced obviously in AST treatment groups than the model group (P<0.05). The activities of 3′-adenylate triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP), total adenine nucleotides (TAN), SOD and GSH-Px were also increased, and the contents of LDH and MDA were reduced significantly (P<0.05). AST treatment also resulted in significant elevations in CT, CF and UM of the isolated uterine smooth muscle and the concentration of Ca²⁺when compared with the model group (P<0.05), especially when the dose of AST was 80 mg/kg. Conclusion AST inhibits the effects on oxidative stress injury of uterus in female rats induced by hypothyroidism, which may be related to its enhancing the activity of antioxidant enzymes, opening Ca²⁺ channel and promoting energy metabolism.