[Objective] This study aimed to establish the criteria for erosive rainfall events under different soil and water conservation measures in runoff plots, and to explore the influencing factors of these criteria. [Methods] Using observational data on rainfall, runoff and sediment yield from 17 standard runoff plots at the Qiaozigou experimental site in the Luoyugou watershed of Tianshui, Gansu Province, in the Loess Hilly Region from 2011 to 2020, frequency analysis and sediment connectivity（IC） assessments were employed to evaluate the criteria for erosive rainfall and their influencing factors under various soil and water conservation measures. [Results] Soil and water conservation measures reduced runoff and sediment yield across different plots. Compared to the control plot, grassland and woodland plots exhibited the most significant reductions in runoff（ 80.39%） and sediment yield（79.78%）. The reduction rate for cropland（47.41%） was notably lower than that for grassland and woodland. Conservation measures elevated the criteria for erosive rainfall, which was ranked in the order of control plot（ 11.62 mm）＜cropland（13.76 mm）＜grassland（18.08 mm）＜woodland（18.26 mm）. The criteria for erosive rainfall showed a negative correlation with the number of runoff events, the connectivity index（IC） and the runoff coefficient, with higher criteria associated with lower IC values, smaller runoff coefficients and weaker hydrological connectivity. [Conclusion] Following soil and water conservation, the hydrological connectivity of slopes decreased, the amount of erosive rainfall reduced, the runoff capacity significantly declined and the criteria for erosive rainfall notably increased, with variations among different measures. This study elucidates the criteria for erosive rainfall on slopes under various soil and water conservation measures and their influencing factors, providing a reference for monitoring soil and water loss on slopes on the Loess Plateau.