This study was based on the monthly and annual rainfall and runoff data of Dongcun hydrological station of the Lianshui basin in the upper reach of Ganjiang river from 1980 to 2010.The M-K trend test，cumulative anomaly method，and double mass curve method were applied to analyze the characteristics of annual distribution，inter-annual trend，and mutation points of rainfall and runoff，as well as the main driving factors attribute to the variation in runoff.The results showed that annual rainfall and runoff averaged at 1 604.8 mm and 6.53×108m3.There was a single peak in terms of the inter-annual variation of rainfall and runoff，and both of them distributed mainly between March and August within a year，which accounted for 72.43% and 75.93% of the annual rainfall and runoff.Influenced by human activities， despite the fact that an insignificant fluctuation increasing trend was found in annual rainfall， an insignificant fluctuation decreasing trend was detected in annual runoff in the Lianshui basin.In addition，the year of 1984，1991，and 2002 were considered as the mutation points of runoff.The inter-annual variation in runoff was affected by rainfall and human activities jointly.The effect of rainfall decreased from 59.05% to 45.45%，whereas the influence of human activities increased from 40.95% to 54.55%.It indicated that variation in watershed runoff was dominantly affected by rainfall at the preliminary stage of soil erosion control，whereas human activities played more and more significant roles gradually with the restoration of vegetation.These results can provide the oretical and practical basis to control soil erosion and the rational utilization of water resources in the upper reaches of Ganjiang river basin.