Qilian Mountain is located in the transition zone between the eastern monsoon region，the Qinghai-Tibet Plateau region and the northwest arid region. It is an important ecological barrier in China. In recent years，due to the impact of human activities such as over-exploitation，over-grazing and grazing，and natural climate change，the ecological environment in the Qilian Mountains has continued to deteriorate. Studying the evolution process and mechanism of multi-time scale ecological environment in this region is of great importance to clarify the good governance countermeasures of Qilian Mountain. The ecological environment evolution of the Qilian Mountains in the multi-time scale shows that the temperature increase in Qilian Mountain and surrounding areas is obvious during the period from 1958 to 2013. The precipitation shows a trend of tortuous growth in fluctuations. The trend of temperature and precipitation shows in the east and west. The obvious spatial difference；the climate change on the millennium time scale in the eastern part of Qilian is mainly wet in the early and middle Holocene，and the late Holocene，especially in the past 2000 years，has a tendency to arid，and the climate in the western part appears in the appropriate period. In the Middle Holocene，the late Holocene showed a trend of humidification；in the past 50 years，the warm and humidification has caused a significant change in the ecological environment of the Qilian Mountains；in the future，the temperature in the Qilian Mountains will continue to face a continuous growth trend，and the precipitation will show a relatively stable situation.