The Hengduan Mountain is located to the southeastern margin of the Qinghai-Tibet Plateau,which is sensitive to climate change and a hot spot for tree-ring research ; it has rich biodiversity and significant climate changes,so it plays an important role in climate change research. Up to now, tree-ring research in this area concentrated on the upper distributional limits, however the systematic study of both the upper and lower distributional limits was out of focus. Based on the dendrochronological method,we established the residual chronologies of Picea likiangensis and Abies georgei at their upper and lower distributional limits by using tree-ring width data,and studied the relationship between the residual chronologies, temperature and precipitation. The study can identify the key climatic factors that affect the radial growth of two conifers. The results showed that : (1) The radial growth of Picea likiangensis was affected by both temperature and precipitation at its lower limits ; there were significant and positive correlations between its growth and November mean temperature (T_(mean)) in the previous year, Tmean of post growing season (September-October) in the current year and July precipitation in previous year. (2) The radial growth of Picea likiangensis was only affected by temperature at its upper limits, by showing a negative correlation with T_(mean) of post growing season in the previous year, and a significantly positive correlation with Tmean of growing season (June-August) in the current year. (3) The radial growth of Abies georgei was only correlated with temperature. November T_(mean) in the previous year and growing season Tmean in the current year positively affected its growth at lower and upper distributional limits respectively. The results of this paper can offer a reference for the study in effects of climate change on tree growth in Northwest Yunnan Plateau, and provide a theoretical basis for the management and protection of forest ecosystems in the area.