Objective In order to investigate the effects of Citrus reticulata Blanco peel extract (CRE) on lipopolysaccharide (LPS)-induced pulmonary inflammation and oxidative stress in rats. Methods In this study, adult male Wistar rats were intraperitoneally injected with 1 mg/kg/d of LPS (14 d) to induce lung inflammation. The rats were randomly divided into 5 groups: control group (Control group), LPS group, LPS + CRE 100 mg / kg group (LPS + CRE100 group), LPS + CRE 200 mg / kg group (LPS + CRE200 group), LPS + CRE 500 mg / kg group (LPS + CRE500 group). Various doses of CRE (100, 200, and 500 mg/kg) were administered in combination therapy (14 d). Serum cell counts and cytokine and oxidative stress biomarker levels of bronchoalveolar lavage fluid (BALF) were measured in each group of rats. The lung morphology of the rats was evaluated by hematoxylin and eosin (H&E) staining. Result CRE decreased the total number of serum leukocytes and the percentage of neutrophils, monocytes, and eosinophils in LPS rats (P<0.05). CRE treatment dose-dependently reduced MDA levels in BALF in LPS rats, but significantly increased SOD and CAT activity (P<0.05). CRE treatment dose-dependently increased the levels of IL-4 present in the BALF of LPS rats, but significantly decreased the levels of INF- γ, TGF- β1, and PGE 2 (P<0.05). Treatment with CRE can significantly reduced the lung histopathological changes induced by LPS administration. Conclusion CRE exerted good effects against pulmonary inflammation by reducing the total number of leukocytes and the percentage of neutrophils, monocytes and eosinophils in rat serum induced by LPS, and by inhibiting excessive oxidative stress and inflammation in the lungs.