Weaning introduces a multitude of stressors that negatively impact feed intake and can diminish gastrointestinal (GI) integrity which leads to increased disease susceptibility and altered gut function. Probiotics have been studied as an alternative to antibiotic growth promoters to enhance gut health. Furthermore, environmental enrichment has been shown to reduce the time spent in negative social interactions and increase feed intake in a stressful environment. The objective of this study was to determine effects of dietary probiotic (Saccharomyces cerevisiae) supplementation on weaning pig growth performance and oxidative stress, with and without environmental enrichment. The experiment was a 2 x 2 factorial design with 2 dietary treatments fed in nursery pens that did or did not include environmental enrichment. Weaned piglets (n=100 and 5pigs/pen; ~25.6 day of age) were allotted to the following dietary treatments: 1) control or 2) yeast probiotic Saccharomyces cerevisiae (0.1% in phase 1 and 2 and 0.05% phase 3 diets) for 5-wks. On days 1, 7, 14, 21 and 35, pig weights, feed intake, fecal scores and blood samples were collected for monitoring diarrhea and measurement of oxidative stress markers. Pen weight (kg) was significantly increased over the five-week period. Pigs fed the basal diet had greater ADG (g) compared to pigs fed the probiotic supplemented diet (overall weeks 460.51 g vs 424.89 g, respectively P < 0.06). Pigs fed the probiotic diet tended to have more solid stool than pigs on the basal diet (P < 0.15). Oxidative stress marker diamine oxidase (DAO) fluctuated over the first 14 days of the nursery trial. There was a significant day effect from day 1, 7 and 14 post-weaning DAO (26.5, 18.3, and 22.1 Ã‚Â±1.4mg/mL respectively; P < 0.0001). In conclusion, probiotic supplementation did not enhance growth performance, but did tend to have improved stool consistency. The environmental enrichment used did not significantly impact growth or systemic oxidative stress. Overall, dietary supplementation and environmental enrichment did not improve weaning pig growth performance and oxidative stress markers in the study.