【Objective】Earthworms are one of the most common soil animals, and generate cast that forms water stable aggregates rich in organic matter. As is known to all, earthworm cast has already been extensively used as organic manure in farmland, because it can promote solubility of the insoluble minerals and increase nutrient elements in the soil. Then how and how much earthworm cast is applied will no doubt affect spatial distribution of the cast in the soil, and little has been reported on impacts of earthworm cast application on soil water dynamics. Therefore in this study, an indoor experiment using simulated soil columns was carried out to explore effects of pattern and rate of the application of earthworm cast on water infiltration in soil.【Method】The experiment was designed to have treatments for earthworm cast application rate, i.e. 50 g·kg^-1, 75 g·kg^-1 and 100 g·kg^-1 and five treatments for application pattern i.e. A: mix cast with soil in the 0~10cm soil layer of the column; B: mix cast with soil in the 10~20 cm soil layer; C: mix cast with soil in the 5~8 cm soil layer; D: mix cast with soil in the 10~13 cm soil layer; and E: mix cast with soil in the 15~18 cm soil layered. So the experiment had 15 treatments (3x5) plus a control (no cast applied) for comparison, and each treatment had 3 replicates. A given amount of water was added to start water infiltration in all the 48 columns. The process of water infiltration lasted 180 minutes. Wetting front movement was recorded and accumulated infiltration calculated for analysis of differences between the treatments. In addition, samples of the soil were collected from each column by layer at the end of the infiltration for analysis of water content.【Result】Results show that the treatments of 50 g·kg^-1 earthworm cast had wetting fronts going deeper than all the others or 4.1 cm deeper to the maximum. Compared with Control group, all the Treatments A, regardless of cast application rate, had wetting front going deeper, and the wetting front was found to be 1, 1 and 0.3 cm deeper in Treatment A50, A75 and A100, respectively, than in Control at the end of the infiltration process. Among the group of Treatment B, Treatment B75 and B100 has wet front going 3% and 11% shallower than Control. When earthworm cast was applied by layer as designed in the experiment, the treatments of cast application rate, regardless of depth of the application, displayed an order of 50 > Control >75 >100 in terms of wetting front depth and the groups of Treatments 75 and 100 inhibited water infiltration, with the effect reducing with increasing application depth. Among the group of Treatments C, Treatments C75 and C100 had wetting front going 6.3% and 19.5% shallower than Control. Among the group of Treatments A, Treatment A75 and Treatment A100 did not differ much from Control in cumulative infiltration, while among the group of Treatment B, Treatment B50, B75 and B100 was 8.2, 7.6 and 11.8 mm respectively, lower than Control, and among the group of Treatments C, Treatment C75 and C100 was 70.7 and 59.7 mm respectively lower than Control (74.2 mm) (P<0.05) at the end of the infiltration. The Kostiakov infiltration model was adopted to fit temporal variation of the measured cumulative infiltration, with determination coefficient R2 ranging from 0.996 to 0.999, which indicates that the fitting is good. In the experiment, water content in the soil-cast mixed layer and the soil layer right underneath increased correspondingly, but with cast application rate being beyond 75 g·kg^-1, water content in the deep soil layer (16~20 cm) might decrease.【Conclusion】It can be concluded that the impact of cast application on water infiltration may vary with pattern and rate of the application. The application of 50 g·kg^-1 earthworm cast in the 0~10 cm soil layer promotes downward movement of the wetting front while the application of 100 g·kg^-1 earthworm cast in the 10~20 cm soil layer significantly inhibits movement of the wetting front depth. The application of cast in layers reduces cumulative infiltration and hence alters soil water redistribution.