[Objective] The differences in aggregate stability and infiltration characteristics of loess under different forest and grass vegetation restoration types were compared in order to provide a theoretical basis for the optimization of ecological restoration patterns in the Loess Plateau. [Methods] Abandoned land (C₁, control), alfalfa land (C₂), natural grassland (C₃), mixed forest land of Pinus tabuliformis and Platycladus orientalis (L₁), and mixed forest land of Robinia pseudoacacia and P. orientalis (L₂) were used to investigate differences in aggregate stability and infiltration characteristics and their exogenous factors. Water-stable aggregate composition and saturated hydraulic conductivity were determined by the Savinov method and a single-ring two-ponding depth infiltrometer, respectively. Mean weight diameter (MWD), geometric mean diameter (GMD), fractal dimension (D), percentage of aggregate destruction (PAD), water-stable macroaggregate content (＞0.25 mm, M_w), and saturated hydraulic conductivity sample (K_s) were used as evaluation indicators. [Results] ① In the 0—30 cm soil layer, C₁ had the lowest GMD and MWD, and GMD and MWD in forest and grass vegetation restoration types followed the order of 〔L₁ and C₃〕＞〔L₂ and C₂〕, respectively, whereas PAD and D showed the opposite order. ② In the 0—10 cm soil layer, L₁ dominated the highest macroaggregate (＞0.25 mm) content (47.24%), followed by C₃ and L₂, while C₁ had the lowest content (24.00%). In the 10—30 cm soil layer, C₃ dominated the highest macroaggregate (＞0.25 mm) content (35.41% at 10—20 cm; 27.96% at 20—30 cm), while L₂ had the lowest content (11.46% at 10—20 cm; 8.00% at 20—30 cm). ③ The variation coefficients of topsoil infiltration characteristics for different restoration types ranged from 0.001 to 0.360. The K_s (0.307 cm/min) of L₁ was the highest, while the K_s (0.044 cm/min) of C₁ was the lowest. ④ Aggregate stability indicators (except PAD) and K_s were significantly correlated with soil organic carbon, porosity, and bulk density. [Conclusion] The restoration of forest and grass vegetation was beneficial for improving aggregate stability and infiltration performance. Compared with natural grassland, long-term forest restoration exhibited better aggregate stability and infiltration characteristics, but those characteristics were worse for short-term forest restoration than for natural grassland. Time accumulation should be emphasized when evaluating the effects of vegetation restoration.