The changes of river runoff and sediment directly reflect the ecological environment and the degree of soil erosion in the basin. In order to explore the variation characteristics of runoff and sediment and its' driving mechanism in the typical soil erosion control area in South China, the runoff and sediment data of Changting section of Tingjiang River Basin from January 1982 to December 2014 were taking as the research object, and the CEEMDAN, Mann-Kendall trend test, Pettitt test and water sediment relationship model were used to analyze the variation characteristics of runoff and sediment. Meanwhile, the double accumulation curve was used to quantitatively study the contribution of rainfall and human activities to the changes of runoff and sediment. The results showed that:(1) The rainfall and runoff in Changting section of Tingjiang River Basin showed no significant decreasing trend, while the sediment rate decreased significantly (p<0.01). The periodicity and trend of runoff and sediment were not synchronous. (2) The sediment transport rate in Changting section of Tingjiang River basin changed suddenly in 2000 (p<0.01). After 2000, the runoff sediment concentration decreased and the inflow sediment coefficient of water sediment relationship curve decreased significantly. (3) The total amounts of runoff and sediment in Changting section decreased after 2000. The contribution rate of human activities to the change of runoff was 68%~81%, and the contribution rate of human activities to the change of sediment was 90%~98%. In human activities, the implementation of soil and water conservation measures dominated by banning management and ecological forest and grass construction were the most important reasons for the reduction of sediment.