This study aimed to investigate the effects of Stevia rebaudiana root polysaccharide (SRRP) on inflammatory responses in obese mice and explore its potential mechanisms. An obesity model was established using a high-fat diet (HFD). Obese mice were divided into a model group, SRRP high-dose group, SRRP medium-dose group, SRRP low-dose group, and a positive control group (atorvastatin calcium, ATV). Each group was administered an equal volume of normal saline, SRRP or ATV for eight consecutive weeks. Serum lipid levels and oxidative stress were measured using biochemical assays. Liver inflammatory factor levels were detected by ELISA. Histological analysis of liver and epididymal adipose tissue was performed using HE staining. Western blot was used to detect the expression levels of phosphoinositide 3-kinase (PI3K), phosphorylated phosphoinositide 3-kinase (p-PI3K), protein kinase B (AKT), phosphorylated protein kinase B (p-AKT), and nuclear factor kappa B (NF-κB). The results showed that compared to the normal group, the body weight of the HFD group significantly increased (P<0.01). HE staining revealed the presence of numerous lipid vacuoles in the liver and enlarged epididymal white adipose tissue cells in the HFD group. Serum lipid levels, oxidative stress, and inflammatory factor levels were significantly elevated in the HFD group(P<0.01). Compared to the HFD group, SRRP and ATV significantly reduced serum lipid levels, oxidative stress, and inflammatory factor levels in obese mice (P<0.01), downregulated the expression levels of p-PI3K, p-AKT, and NF-κB proteins (P<0.01), alleviated hepatic lipid accumulation, and reduced the size of epididymal white adipose tissue cells. These findings suggest that SRRP can improve lipid levels, hepatic lipid accumulation, and inflammatory responses in obese mice, and its mechanism may be related to the inhibition of the PI3K/AKT/NF-κB signaling pathway.