[Objective] The hydrologic regime change in typical watershed on Loess Plateau was studied, and its attribution analysis was carried out, in order to provide scientific support for soil and water conservation and efficient utilization of water resources in different regions of the Loess Plateau. [Methods] Sandu River (a tributary of Weihe River) and Dali River (a tributary of Wuding River) were selected as the study areas, and the traits in variations of streamflow and their driving factors from 1965 to 2018 were analyzed based on meteorological and hydrological data at Gangu and Suide hydrological stations by using the linear regression, Mann-Kendall test, accumulated anomaly, and double mass curve methods. The improved range of variability approach was employed to analyze the impact of the hydrological alterations in different river by soil and water conservation dominated by terracing and damming. [Results] The annual runoff showed significant decreasing trends(p<0.01) and the abrupt changes occurred in around 1990s in Sandu River and Dali River. The alteration degree of runoff in Sandu River was high (90.12%) and in Dali River was moderate (60.66%) calculated by the improved range of variability approach (RVA) method. Among 32 indicators of hydrologic alteration (IHA), the rise and fall rate of flow were affected most significantly. [Conclusion] In the Sandu River (dominated by terracing), both the magnitude of monthly median flow and the annual minimum flow decreased dramatically, timing of annual minimum flow delayed and duration of low pulses increased. In the Dali River (dominated by damming), the magnitude of monthly median flow depended on the seasonal alteration. The annual 1-day and 3-day minimum flow increased and frequency of low pulses declined.