A total of eleven ecological factors values were obtained from the ecological suitability database of the geographic information system for traditional Chinese medicines production areas (TCMGIS), and the relationships between the chemical components of Dendrobium and the ecological factors were analyzed by partial least square (PLS) regression. There existed significant differences in the chemical components contents of the same species of Dendrobium in different areas. The polysaccharides content of D. officinale had significant positive correlation with soil type, the accumulated dendrobine in D. nobile was significantly positively correlated with annual precipitation, and the erianin content of D. chrysotoxum was mainly affected by air temperature. The principal component analysis (PCA) showed that Zhejiang Province was the optimal production area for D. officinale, Guizhou Province was the most appropriate planting area for D. nobile, and Yunnan Province was the best production area of D. chrysotoxum.