Abstract: Douglas fir(Pseudotsuga sinensis), as a kind of the national class Ⅱ endangered tree species, has been attracting comparatively less attention on its dendroclimatology so far instead. A standard tree-ring width chronology was established based on the tree-ring sample cores collected from Zhenping county, Ankang City, Shaanxi Province. Pearson correlation was introduced to analyze the correlation of tree-ring width index to the precipitation, the temperature as well as the PDSI. Results show that the width of Douglas fir was mainly affected by precipitation and air temperature, which was significantly positively correlated with the total precipitation in the growing season (r=0.386, P < 0.05), negatively correlated with the average maximum temperature in November of the previous year (r=-0.364, P < 0.05), and positively correlated with PDSI in October of last year (r=0.485, P < 0.01). In addition, under the background of global warming, the monthly average maximum temperature may inhibit the radial growth of Douglas fir. Studying the response of tree-ring width to temperature and precipitation, and understanding the influence of climatic factors on the tree species of Douglas fir in the research area can provide theoretical basis for relevant departments in the climate change study of this region.