Abstarct: A new water-soluble polysaccharide with molecular weight of 35.2 KDa and a specific optical Rotation of + 178.5° was extract by warm water (50C°) from the roots of Acanthophyllum glandulosum. The polysaccharide purified through DEAE-cellulose and Sephadex G-100 columns. Total yields of crude and purified polysaccharides were 3.45% and 2.38% respectively. The purified polysaccharides had no absorption at 280 nm (Detected by UV Spectrum). Total carbohydrate content of purified polysaccharide was 98.2% Monosaccharide analysis by GC revealed that polysaccharide was composed of Glucose, Galactose, Arabinose and Mannose with a relative molar ratio of 2.9: 6.1: 0.9: 1.0 respectively. Its structural features were elueidated by a combination of chemical and analytical methods such as methylation, partial acid hydrolysis, periodate oxidation and smith degradation, FT-IR and 13C and 1H NMR Spectroscopy. The data obtained indicate that polysaccharide possessed a backbone of α-(1→6)-lixnked Galactose with branched attached to O-2 by α-1-lixnked Mannose and at O-3 by α-(1→3)-lixnked Glucose and by α-(1→3)-lixnked Arabinose.