After long-term soil erosion control on the Loess Plateau, the sediment problem has been effectively solved, but the impact of vegetation restoration and terrace construction on the spatial transport of sediment has not been fully revealed. This study uses land use data and Landsat images to determine the distribution of terraces and vegetation coverage, and uses vegetation coverage and crop management factors and engineering factors, which could characterize the resistance of vegetation and terraces to sediment transport, to calculate sediment. The index of connectivity (IC) was applied to analyze the temporal and spatial dynamic changes of sediment connectivity, the combined effects of vegetation and terraces on sediment connectivity of typical watersheds in the third subregion of the Loess Plateau are quantified. Weighting factors were adjusted to simulate the calculation of the sediment connectivity index under different scenarios and analyze the separate effects of vegetation and terraces on sediment connectivity. The results showed that IC significantly decreased from -3.42 to -9.17 in 35 years (1986-2020) due to the rapid vegetation restoration and the large-scale construction of terraces. The scenario simulation found that the terraced fields were the main driving factor for the weakening of sediment connectivity between 1986 and 1999. After 1999, vegetation and terraced fields worked together. The IC under the influence of vegetation decreased by 73.05% from 1986 to 2020, and the IC under the influence of terraced fields decreased by 26.75% from 1986 to 2020. In space, terraces and areas with high vegetation coverage showed weak sediment connectivity, while the main ditch and some branch ditch areas in the middle and lower reaches have strong sediment connectivity. In general, vegetation restoration and terrace construction decreased the sediment transport capacity, and the sediment transport paths in the basin were concentrated in the middle and lower reaches of the main ditch and some branch ditch areas. The results of this study can help to deepen the study of sediment changes under the influence of vegetation restoration and terrace construction in small watersheds in the loess hilly area.