Abstract: Internal erosion and transport of fine particles may be induced by the seepage and infiltration of rainwater into a slope. In this study, the interaction between the transport of fine particles and the infiltration in a soil slope is investigated. A slope stability model considering coupling of seepage and internal erosion is established. The effects of the initial saturated permeability and air-entry value parameter on the slope stability and seepage are studied. The results of an illustrative example show that the internal erosion occurs mainly in the zone within the wetting front, which accelerates the advance of the wetting front and the slope stability is reduced consequently. The initial saturated permeability and air-entry value parameter are the main factors to affect the internal erosion in the slope. When the saturated coefficient of permeability is greater, the effect of the internal erosion on the infiltration and slope stability becomes more significant as long as the rainfall flux is equal or greater than the saturated coefficient of permeability. When the air-entry value of the soil is greater, the influence of the internal erosion on the infiltration and slope stability becomes less significant.