Abstract: To determine the optimum harvest time of Polygonatum cyrtonema in Yunnan, the polysaccharide content, fresh and dry weight of P. cyrtonema were determined in different growing years and different harvest months in Jinping County, Yunnan Province. The results showed that the polysaccharides content of each section of five years old P. cyrtonema decreased with the increase of the growing year, and the content of polysaccharides in 1-3 years’section was relatively high, which was 128, 121, 97 mg/g, that in 4-5 years’ section reduced to 67 mg/g and 58 mg/g; in different harvest months, the content of polysaccharides was higher in December (131.11 mg/g) and next January (133.85 mg/g), respectively, and the fresh weight of rhizome was the highest in December, reaching 821.41 g, and the drying rate was 26.51%. The most suitable harvesting period of P. cyrtonema in Yunnan Province should be at the end of December and the beginning of next January, and the best harvest time of P. cyrtonema with rhizome propagation is 3 years.