In order to investigate the potential of Astragalus polysaccharides to inhibit mastitis in dairy cows and assess its impact on milk quality.40 cows with mastitis were selected at random and divided into four groups, with 10 cows in each group. These were designated as the control group, experimental group A, experimental group B and experimental group C, respectively. The control group was fed a standard diet, while the experimental groups A, B and C were fed 20, 40 and 80 grams of Astragalus polysaccharides per head, respectively. The changes in the intake of feed, weight and milk yield of dairy cows were recorded and quantified. Following the feeding period, the number of somatic cells and the contents of milk protein and milk fat were quantified. Concomitantly, the alterations in glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), total antioxidant capacity (T-AOC) and malondialdehyde (MDA) in serum were quantified. To assess the impact of astragalus polysaccharides on antioxidant activity.The administration of astragalus polysaccharides has been demonstrated to effectively regulate the weight and feed intake of dairy cows, increase milk yield, reduce somatic cell number and increase milk fat content. In terms of antioxidant activity, it can up-regulate the expression of GSH-Px, SOD and T-AOC, and reduce the content of MDA, indicating that it can enhance the antioxidant capacity of dairy cows to some extent. The optimal dosage is 40 g/head·d and 80 g/head·d, which demonstrates a dose-dependent manner.It has been demonstrated that astragalus polysaccharides can effectively reduce mastitis in dairy cows. This may be due to their ability to enhance the antioxidant capacity of the cows and improve their production performance. It has been demonstrated that a certain quantity of astragalus polysaccharides can be incorporated into the breeding process, thereby enhancing the body characteristics and ensuring the stable milk production efficiency.