Abstract Poor maternal nutrition during gestation is common in livestock production and includes both nutrient restriction and over-nutrition. Poor maternal nutrition affects offspring pre- and post-natal growth including decreases in muscularity and increases in adiposity which results in poor quantity and quality of animal products. Oxidative stress, when free radicals exceed the capacity of antioxidants, damages lipid membranes, proteins, and DNA. Oxidative stress may contribute to the poor growth outcomes observed in offspring from poorly nourished dams. Therefore, the objective of this research was to determine the effects of poor maternal nutrition during gestation on offspring circulating oxidative status in sheep. We hypothesized that offspring of restricted- and over-fed ewes would have an altered oxidative status in circulation. To test this hypothesis, multiparous Dorset ewes (n = 45) pregnant with twins were fed 100% (CON), 60% (RES), or 140% (OVER) of National Research Council requirements from d 30 of gestation until parturition. At parturition, ewes were fed a control diet such that the nutritional insult only occurred during gestation. Blood samples were collected from offspring by jugular venipuncture at d 112 and d 224 of age to evaluate oxidative status in circulation. Data were analyzed in SAS 9.4 using PROC MIXED with fixed effects of offspring sex and maternal diet with sampling timepoint as repeated measure. Data were considered significant at P < 0.05. In offspring plasma, superoxide dismutase, an endogenous antioxidant, activity was 17% greater in CON offspring compared with RES and OVER (P ≤ 0.04). Malondialdehyde (MDA), a marker of lipid peroxidation, concentration was not different at d 112 but RES animals had 10% lesser concentration of MDA than CON at d 224 (P ≤ 0.02). Protein carbonyl (PC), a marker of protein oxidation, concentration was 9% greater in CON animals than RES and OVER (P = 0.01). Additionally, PC concentrations were 19% greater at d 224 compared with d 112 (P ≤ 0.001). These results indicate that at the chosen timepoints, RES and OVER offspring had less antioxidant activity but also less indication of oxidative damage. Overall, the alterations in antioxidant activity and oxidative damage suggest dysregulation in circulating oxidative status that may contribute to the negative consequences of poor maternal nutrition during gestation. Future work should focus on the impacts of poor maternal nutrition on oxidative stress in muscle.