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Runoff and sediment data from 1987 to 2010, 143 flood events of Qiaozi East watershed (QE) on the loess plateau were used to investigate the relationships among rainfall, runoff and suspended sediments. K-means clustering of different rainstorm patterns was used to differentiate watershed runoff and sedimentation features and to quantify the impacts of erosion control practices on runoff and sediment production. The results indicated that the precipitation (P) and the maximal 30 minutes rainfall intensity (I30max) were the most relevant factors to runoff and sediment responses. The rainfall events were divided into four rainstorm patterns, as Pattern Ⅰ (low P and low I30max), Pattern Ⅱ (high P and high I30max), Pattern Ⅲ (high P and low I30max) and Pattern Ⅳ (low P and high I30max). The runoff generated by the storms, in term of peak discharges from low to high were in the order of Pattern Ⅱ storms, Pattern Ⅳ, Pattern Ⅲ and Pattern Ⅰ. Pattern Ⅱ, though the fewest in occurrences, produced the most sediments while Pattern Ⅳ, Pattern Ⅲ and Pattern Ⅰ storms produced limited sediments with no significant differences. The soil and water conservation practices significantly reduced runoff and sediment of the watershed, especially for the highest sediment production events of Pattern Ⅱ.