Based on the data of runoff coefficient from 1960 to 2005 in Weihe River basin, the paper divided Weihe River basin into five regions such as the upstream of Beidao, Beidao-Linjiacun,Linjiacun-Xianyang,Xianyang-Lintong(including Zhangjiashan),Lintong-Huaxian+Zhuangtou. It analyzed the basic statistical characteristics, inter-annual variation of runoff coefficient of the five regions, used R/S analysis method to conduct persistent analysis and took Kendall rank correlation test to conduct trend analysis,used the method of power spectrum to computer period,combined Mann-Kendall and accumulative departure curve method to analyze mutation. The results showed that the runoff coefficient of Weihe River basin presents a significant decreasing trend and will continue to decrease. The notable period in the upstream of Beidao is 3 years.The notable period in Beidao-Linjiacun is 2.66 years, all of the other regions have no notable cycle. Runoff coefficient mutation occurs in late 1960s and early 1970s, late 1980s and early 1990s. Due to the impacts of human activities and climate change, the transfer capacity from rainfall to runoff in whole Weihe River basin presents a significant decreasing trend and will continue to decrease.