Soil and water conservation engineering is an effective measure to prevent water loss. In the semi-arid watershed of the Loess Plateau, reasonable soil and water engineering development can utilize the limited precipitation, thus promoting vegetation restoration. In the current study, typical soil and water engineering (e.g., fish scale pits and adversely graded tableland) in a small watershed located in Dingxi City, Gansu Province were selected, and natural slope with the same vegetation served as a control. Soil samples at each site were collected from depths of 0-20, 20-40, 40-60, and 60-80 cm. Soil particle size distribution was analyzed. Soil water retention curves were monitored and simulated by Brooks-Corey, Gardner and van-Genuchten models. The results indicated that, the effects of soil and water conservation engineering on soil particle size distribution varied with soil depth. For the soil particle size distribution, the clay content of adversely graded tableland (10.63%) and fish scale pits (9.78%) was significantly higher than that of the control (9.66%). Meanwhile, the silt content of adversely graded tableland (71.42%) and fish scale pits (70.74%) also was significantly higher than that of the natural slope (67.85%). Compared with control, soil saturated hydraulic conductivity can be improved by 53.5% and 46.9% in the adversely graded tableland and fish scale pits, respectively. The Brooks-Corey, Gardner, and van Genuchten model can well fit the soil water retention curve of different soil and water engineering approaches. Compared with control, soil available water in adversely graded tableland and in fish scale pits can be increased by 15% and 9%, respectively. The effects of soil and water engineering on the soil available water in the surface soil layer were more pronounced after long-term implemention of soil and water engineering.