Abstract: Abstract: A sloping farmland has been widely considered a major contributor to the sediment yield in Southwestern China. Numerous measures have also been launched to control soil erosion and land degradation in recent years. Among them, the soil bund has been widely adopted for the water flow regulation of soil conservation or land reconstruction in the sloping farmlands. However, the stability of the bund depends mainly on the crack seepage under the soil conservation. The objective of the present study is to reveal the features of water seepage in the soil bunds under different degrees of crack development on the purple-soil sloping farmlands. Photography and laboratory digital image processing were also carried out to determine the degrees of crack development for the bunds in the Beibei District, Chongqing of China. Three typical purple soil bunds were selected as the cases for infiltration experiments, including the heavy, medium, and slight crack developments. The double-ring and four infiltration models were applied to simulate the infiltration process, such as the Kostiakov, Mezencev, Horton, and Phillip model. The results showed that: 1) The Crack Area Ratio (CAR) was applied to establish the four types of crack development degrees, including the slight (CAR≤3.5%), medium (3.5%?CAR≤6%), heavy (6%?CAR≤10%), and extremely heavy development crack (CAR?10%). 2) The infiltration processes of all soil bunds dropped steeply, then decreased slowly till stable. The infiltration rate of crack development bunds was also much higher than that without cracks, where the difference also decreased with time. Correspondingly, the soil permeability was significantly improved with the enhancement of crack development degrees. However, there was an outstanding difference in the increment of initial infiltration rate, the mean infiltration rate, the stable infiltration rate, and 120 min cumulative infiltration, among the testing crack development degrees from no crack development to heavy development crack. The maximum increment occurred in the initial infiltration rate (98.72%), 1.01, 1.12, and 1.02 times than that of the mean infiltration rate, stable infiltration rate, and 120 min cumulative infiltration, respectively. 3) The capability of soil infiltration under different degrees of crack development was still highly correlated with the intensity of crack development after removing the influence of initial moisture content. The maximum depth of crack and the ratio of Area And Perimeter (RAP) were significantly positively correlated with the initial infiltration rate, the mean infiltration rate, and 120 min cumulative infiltration (P<0.05), whereas, the CAR was only significantly positively correlated with the mean infiltration rate (P<0.05). 4) The Kostiakov model and Mezencev model presented the better fitting to simulate and predict the bund infiltration under the different degrees of crack development (with a mean R2 of 0.95 and 0.94, respectively), followed by the Horton model (the mean R2 of 0.83). The Phillip model was the lowest in fitting on the soil infiltration with the mean R2 of 0.74. The Kostiakov model can be only applied to effectively represent the infiltration state of the bund with the development of the cracks when the infiltration time period is specified. But it gives rise to an infiltration rate value of zero when the infiltration time becomes infinite, no infiltration could reach a real state in the field. The findings can provide a strong reference for the instability mechanism of crack development in the bunds construction, maintenance, and rational utilization on the purple soil sloping farmlands.