To study the composition and activity of polysaccharides in the alcohol precipitate from Renshen Guben Oral Liquid，with the aim of achieving comprehensive utilization of Chinese medicinal resources.Methods:High-performance liquid chromatography(HPLC) was used to analyze the monosaccharide composition.An intestinal microecology imbalance model in male Balb/c mice was constructed using lincomycin hydrochloride to study the microecological regulation effect.The experimental groups included the natural recovery group，a bifidobacterium(Lizhu Changle) group(0.5×109 CFU/mL of Lizhu Changle solution)，low-dose polysaccharide group(75 mg/kg)，and high-dose polysaccharide group(150 mg/kg).The effect on immune function was assessed through a series of experiments，such as spleen lymphocyte transformation assay using ConA，antibody-forming cell detection，and natural killer(NK) cell activity measurement.Negative control group，low-dose polysaccharide group(75 mg/kg)，and high-dose polysaccharide group(150 mg/kg) were set up.Results:The polysaccharide content in the alcohol precipitate of Renshen Guben Oral Liquid was 68.5%，and the composition included ten monosaccharides，including rhamnose，arabinose，galactose，galacturonic acid，anhydrous glucose，glucuronic acid，mannose，xylose，fucose，and ribose.Compared with the natural recovery group，both the low-dose and high-dose polysaccharide groups significantly improved the intestinal microbiota imbalance in mice(P<0.05)，with the high-dose polysaccharide group showing better effects than the Lizhu Changle group(P<0.05).Compared with the negative control group，the high-dose polysaccharide group significantly promoted lymphocyte proliferation(P<0.05)，increased the number of antibody-forming cells(P<0.05)，and enhanced NK cell activity(P<0.01).Conclusion:The polysaccharides in the alcohol precipitate of Renshen Guben Oral Liquid are primarily composed of ten monosaccharides，including anhydrous glucose and galactose.The polysaccharides from the residue can regulate the intestinal microecology and enhance immune function，offering significant potential for development and utilization.