In order to evaluate the applicability of dynamic high-pressure microfluidization (DHPM) for the extraction of polysaccharides from Polygonatum kingianum Coll. et Hemsl. (PKP), the effects of DHPM assisted extraction on the yield, structural characteristics (molecular mass, viscosity, monosaccharide composition, and infrared spectrum) and functional properties (1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, α-glycosidase inhibitory activity and tyrosinase inhibitory activity) of PKP were evaluated in comparison with traditional hot water extraction. The results showed that compared to traditional hot water extraction, DHPM assisted extraction led to a 1.63-fold increase in the yield of PKP, decreased its molecular mass and viscosity by 27.90% and 29.04%, respectively, changed its monosaccharide composition, and increased its DPPH radical scavenging capacity and α-glycosidase inhibitory activity, but had little effect on its main structure or tyrosinase inhibitory activity. To sum up, DHPM has obvious advantages in improving the extraction yield and antioxidant and hypoglycemic activities of PKP and therefore is a promising method for PKP extraction. This study will provide a scientific basis for the high-efficiency extraction of PKP.