Using tree ring of Picea schrenkiana sampled from the upper treeline in the Middle and East of Boertala Mongolia Autonomous Prefecture,JPK tree - ring width standardized chronology was established to analyze the characteristics of the chronology and their responds to climate factors. The JPK chronology was found having correlation with the annual mean minimum temperature of Bole and Jinghe stations. Annual mean minimum temperatures of middle and east of Boertala Mongolia Autonomous Prefecture were reconstructed by the tree - ring width standardized chronology,which explained 34. 3 ﹪ of the variance in the reconstruction (F = 25. 611,P < 0.0001). After analyzing,it was found that there were 7 warm and 7 cold periods in the area in recent 517 years. The temperature reconstruction has a good response to the temperature reconstructions from tree - ring and glacial change. The results revealed the common climatic extremes and climate change over north - west China. The power spectrum analysis shows that there were 3a,3. 8a and 5a cycles in our reconstruction,which may be associated with ENSO. The moving t - test indicates that the significant abrupt changes were presented in about 1568A. D.,1667 A. D.,1708 A. D.,1734 A. D. and 1845 A. D.