Purpose: To investigate the effect of crude polysaccharide isolated from pao-tian-xiong on chronic renal failure in mice, and its monosaccharide composition. Methods: Male Kunming mice were orally treated with adenine (211.5 mg/kg/day) for 7 days, followed by either crude polysaccharides (125, 250 or 500 mg/kg), or positive drug solution (jinguishenqi pill, 2000 mg/kg) for another 7 days (each group had 15 mice). Mice in normal and negative control groups were given saline. Mental and physical states, blood urine nitrogen (BUN) and serum creatinine (SCr), kidney morphological changes and organ indices were determined. Histopathological examination of spleen and kidney tissues was also performed. The monosaccharide composition of crude polysaccharide was determined by high-performance liquid chromatography (HPLC) and gas chromatography and mass spectrometry (GC-MS). Results: Compared with negative control group, serum BUN (6.71 mmol/L vs. 8.61 mmol/L) and Cr (107.74 vs. 113.39 μmol/L) were significantly decreased by the crude polysaccharide isolate (p < 0.05), whereas epididymis index (0.2556 vs. 0.2135 %) and seminal vesicle index (0.5547 vs. 0.3945 %) were increased (p < 0.05). Histopathological examination showed that injuries to kidney, spleen, testis and epididymis decreased significantly. The crude polysaccharides contained mainly glucose, rhamnose, arabinose, galactose, mannose, galacturonic acid, glucuronic acid and xylose, and their contents ranged from 0.7 to 65 %. Conclusion: These results suggest that the crude polysaccharides of Pao-tian-xiong ameliorates CRF symptoms in mice, thereby providing experimental evidence in support of its use as an anti-CRF drug.