Abstract: In order to better understand the runoff response to climate change in the upper reaches of the Yellow River, we develop joint distribution models base on multivariate Copula theory. And obtain the quantitative relationship between the main climate factors and runoff changes through the analysis of multiple dependent structures. The results show that the runoff at the JiMai gauging station affected by climate change obviously. In the past 53 years, the Copula dependent degree index of runoff and major meteorological factors, such as temperature, precipitation, potential-evaporation capacity (Penmanand-Monteith formula) are 0.03, 0.46, 0.13, while the dominant influencing meteorological factors of runoff changes are not the same for different stages. Recharged from precipitation, ice and snow, permafrost melt water and groundwater, the runoff show a complex evolutionary process.