Taking the importent rivers in Zhejiang Province as the research object, water and sediment series data from 1956 to 2013 of 11 the hydrology stations were chosen to analyze the characteristics of the intraannual, interannual, and decade variations of the runoff and suspended sediment discharge. The methods such as the improved Mann - Kendall (M - K) trend test and linear sliding regression method were used to systematically analyze the runoff and sediment variation of the 6 major rivers. The results show that the intraannual and interannual variations of the runoff and sediment have certain corelation; the change amplitude of sediment is greater than that of the runoff; the trend of runoff variation is not significant, however, the sediment discharge of seventy-three percent of the hydrological stations decreased significantly.