Abstract: Objective To study the protective role of polysaccharides from Boschniakia rossica in cellular oxidative injury induced by hydrogen peroxide (H₂O₂) in Chang liver cell line.Methods The oxidative damage model was established in Chang liver cells with H₂O₂,then the cell viabilities were detected with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and the levels of lactate dehydrogenase (LDH),alanine aminotransferase (ALT),aspartate aminotransferase (AST),malondialdelyde (MDA),reduced glutathione (GSH),and superoxide dismutase (SOD) were measured with spectrophotometric methods.Results H₂O₂ (300 μmol/L)resulted in the inhibition of cell viability(52±1.2%),the leakage of LDH(595.4±5.6 U/L),ALT (23.5±2.9 U/L)and AST (29.4±2.9)U/L into culture fluid,decreased content of SOD (163.1±6.1 U/mg prot) and GSH (8.91±1.26 mg/g prot),and increased content of MDA (12.6±2.6 nmol/mg prot) in Chang liver cells.At the concentration of 12.5-200 m/L,polysaccharides from Boschniakia rossica showed no toxic effect on cultured Chang liver cells;however,Boschniakia rossica polysaccharides at concentration of 50 mg/L induced an increase in cell viability (79.0±5.5%),reductions of LDH (374.4±12.5)U/L,ALT (10.4±2.9 U/L) and AST (14.4±3.2 U/L) leakage,increased of SOD (323.6±17.3 U/mg prot) and GSH level (15.4±0.52 mg/g prot),and reduction of MDA formation (6.93±0.75 nmol/mg prot) in Chang liver cells with oxidative damage.Conclusion Polysaccharides from Boschniakia rossica has protective effect on oxidative damage induced by H₂O₂ in Chang liver cells.