Abstract: By the methods of stepwise regression, principal component analysis, and grey relational grade analysis, this paper studied the correlations between the effective components (polysaccharides and water and alcohol-soluble substances) contents and antioxidant activity of wild Polygonatum odoratum in different places and the ecological factors. Among the test ecological factors, the mean air temperature in January and in July, mean annual precipitation, frostfree period, and soil pH and total potassium were the main factors affecting the effective component contents of P. odoratum, with a contribution rate of 99.0%. As compared with soil factors, climatic factors made more contribution to the effective component contents. Soil total potassium was the key factor controlling the effective component contents, mean annual precipitation was the main decision factor, and mean air temperature in January was the main limiting factor. The plant polysaccharides and watersoluble substance contents were the key factors affecting the antioxidant activity of P. odoratum, and the capability of P. odoratum in excavating DPPH free radical increased with increasing contents of  polysaccharides and watersoluble substances.

Key words: Polygonatum odoratum, ecological factor, effective component, stepwise regressionanalysis, grey relational grade analysis.