Abstract: Abstract: Understanding the seepage characteristics of loess preferential flow is important for loess landslide risk control. In order to study the seepage characteristics of loess preferential flow, in this study, eight test pits were designed in 2 regions of the abandoned farmland in Nanyuan Dongfeng village, Jingyan county, China (108°50′48″E, 34°29′25″N). The soil was developed in loess parent material. In each region, soil texture was homogenous without obvious macropore and cracks. The test pits were labeled with 1#-8#. In region I, the first 3 pits had same size, but different designed infiltration amount with 30, 60 and 90 mm, respectively. The 4# pit was similar with the 2# pit, but the former had high initial soil moisture. The 5#, 6# and 7# were same with 1#, 2# and 3#, respectively but in the region II. The 8# pit was similar with 4#, but had a bigger size. The dye tracer method was conducted and the soil profile was pictured. The images after binarization were used for preferential flow characteristics analysis. The infiltration depth and amount non-homogeneous coeffeicients were determined. The fractal dimension and fractal feature parameter were also determined. The results showed that infiltration had an obvious impact on the infiltration depth. The nonuniformity of the preferential flow infiltration depth became more obvious with increasing infiltration. However, the nonuniformity of the preferential flow infiltration depth was less obvious when the initial moisture content was high. The development of the preferential flow was lower, its velocity was higher, the average infiltration was greater and the fractal dimension was smaller. The loess porosity size also significantly influenced the correlation coefficient of the preferential flow infiltration depth. The nonuniformity of the infiltration coefficient and the nonuniformity of the preferential flow infiltration depth became more obvious and the fluctuation range of depth thresholds was greater when porosity increased. The test scale of loess for the same treatment did not show an appreciable effect on the fractal dimension of the wet peak trace. Within the 0-0.5 times of maximum infiltration depth of preferential flow in southern tableland in Jingyang County, when the value of the fractal characteristic was high, the nonuniformity of the preferential flow was higher, and the preferential flow was more developed. Without obvious preferential flow seepage channel, the maximum infiltration depth was less than 120 cm under irrigation water volume of 90 mm. Considering normal evaporation and no crack, we considered that the surface irrigation water was not easy to directly lead to the rise of ground water level. Therefore, the preferential flow plays an important role in the whole process from the surface water to the groundwater. At the same time, the influence of preferential flow on loess landslide should not be ignored.