The Qilian Mountain is an important ecological security barrier in western China，and also an important water source for the Yellow River and many inland rivers. The assessment on dynamic change of ecological functions in the Qilian Mountain’s mountain-river-forest-field-lake-grassland-desert system in 1985-2020 is carried out based on the comprehensive monitoring data set of the sky-ground integrated monitoring system. Main findings of assessment are as follows：（1）The combined dynamic degree is 0.07%，0.13%，and 0.21% in the pan-Qilian-Mountain region，the Qilian Mountain，and the Qilian Mountains National Park respectively；in 2020，the area of ice/water has shrunk by 42%，the water area has increased by about 23%，the area of other ecosystems has increased slightly，and the proportion of forest，field，lake and grass has changed slightly mainly due to the increase in the water area，compared with 1985；（2）over 35 years，NPP of all ecosystems，except for woodland，in the pan-Qilian-Mountain region has showed a significant increasing trend，with NPP of ecosystems for wetland，scrubland，grassland，bare land and arable land sequenced in order of growth rate，while NPP of woodland has showed a significant decreasing trend，with the average value of multi-year NPP in the region being about 67 gCm^-2a^-1；in the pan-Qilian-Mountain region，NPP of Qinghai Lake basin and Datong River-Huangshui River basin has showed a insignificant variation trend，while NPP of other basins has showed a significant increasing trend；NPP in the Qilian Mountain region and the Qilian Mountains National Park has showed a significant increasing trend，among which，the woodland NPP in the Qilian Mountain region at 2400-3300 m and the Qilian Mountains National Park at 2400-3200 m has showed a significant decreasing trend；（3）the carbon sequestration in the pan-Qilian-Mountain region，the Qilian Mountain region，and the Qilian Mountains National Park has showed a fluctuating upward trend，of which the carbon sequestration in the Qilian Mountain region and the Qilian Mountains National Park has been dominated by grassland carbon sequestration；（4）the precipitation in the mountainous area centered on the upper reaches of the Heihe River has accounted for 55.5% of the regional sum，with evapotrans-piration accounting for 49.3%，runoff accounting for 87.8%，and water production accounting for 66.4%. The mountainous area has a dominant role in the water conservation of the whole region，in which the grasslands dominated by alpine meadows and alpine grasslands are the main ecosystem of water conservation. From 1985 to 2010，each component for water conservation of the Qilian Mountain has fluctuated and rose，and then showed a decreasing trend since 2010. The results of the above study provide scientific basis and data support for the systematic and in-depth understanding of the ecological functions of the Qilian Mountain’s mountain-river-forest-field-lake-grassland-desert system，and can serve the green development of the pan-third pole.