Chemical structure of Polygonatum kingjanttm polysaccharides was determined Fourier-transform infrared spectroscopy (FTIR) and circular dichroism (CD). Micromorphology of polysaccharides was observed by scanning electron microscopy (SEM). Thermal stability of polysaccharides was evaluated by thermogravimetric analysis (TGA). And effects of Polygonatum kingjanttm polysaccharides on α-glucosidase and α-amylase were investigated. The results suggested that there were pyranosidic linkages in Polygonatum kingjanttm polysaccharides. And Polygonatum kingjanttm polysaccharides might be acidic polysaccharides containing uronic acids. Polysaccharides exhibited positive cotton effect at wavelength of 210 nm. Micromorphology of polysaccharides included porous sheet-like structure and multichain aggregation structure. The loss rate of polysaccharides was high at 248~350 ℃, followed by 30~200 ℃ and 400~700 ℃. Polygonatum kingjanttm polysaccharides did not effectively inhibit α-amylase, but drastically inhibit α-glucosidase with IC50 (concentration that inhibited enzyme activity by 50%) of 4.572 g/L.