In order to explore water hold capacity of water storage clay and improve soil water movement characteristics of the Loess Plateau, the water retention test of water storage clay and the indoor infiltration and evaporation test of soil column with water storage clay layer were carried out. Three particle size levels (20~30, 5 and 2 mm) were set for water storage clay. The thickness of water storage clay layer over the soil column was 5 cm, and the treatment without water storage clay was used as control (CK). The results showed that when the room temperature was 15 ℃, three particle sizes of water storage clay could reach saturation within 40s, and the water absorption rate was between 30%~90%. Meanwhile, the water release rate was relatively slow, so it indicated that the water retention of water storage clay was better. In terms of the infiltration of the soil column, the migration distance of wetting front was significantly promoted by water storage clay with different particle sizes, and the cumulative infiltration amount increased by 40%~60% compared with CK, and it increased with the increasing of the particle size. In terms of soil column evaporation, after continuous evaporation of seven days, soil evaporation was inhibited in varying degrees by water storage clay with different particle sizes. Moreover, the inhibition effect was the most obvious when the particle size was 5 mm, its accumulated evaporation was 67.23% lower than that of CK. The overlying water storage clay layer could reduce the loss of soil water. The soil moisture content in the 10—25 cm soil layer of the soil column covered by water storage clay with different particle sizes increased by 4~5 times compared with CK. With comprehensive consideration of soil infiltration and evaporation, the effect was the best when the particle size of water storage clay was 5 mm. This study could provide theoretical basis for constructing methods to improve the infiltration and storage capacity of slope on the Loess Plateau.