The paper analyzes the change characteristics and trend of runoff and sediment using water and sediment data observed in the coarse sand source regions of the Loess Plateau from 1960 to 1999.The changing characteristics of runoff and sediment had a great variation during the study period.Concentrated time for runoff occurrence in the studied watersheds was in August,except Tuwei River watershed where the time was in July.Concentrated time for sediment occurrence in the studied watersheds was all in August.Abruptly changed time for both runoff and sediment in the five watersheds was all in the 1970's and after that time,runoff and sediment had a decreased trend,especially in 1990's.Human activities and climate change are the main influence factors.