Abstract: Studies of rill flow hydraulic characteristics are essential to understand the mechanism of rill erosion and develop soil erosion prediction models. This paper presents an analysis on hydraulic characteristics of the rill flows on slope land based on a series of runoff scouring laboratory experiments for the conditions of different soil bulk densities (1.2, 1.35 and 1.5 g/cm3), flow discharges (2, 4, 8 and 16 L /min), and land slopes (5°, 10°, 15°, 20° and 25°). The results show that both flow discharge and land slope are important factors influencing flow velocity. And flow velocity can be expressed in a power function of land slope and flow discharge with the former as the major factor; soil bulk density has a certain influence on flow velocity and its effect varies with land slope. The Reynolds number, varying in the range of 248 to 1932, is independent from soil bulk density or land slope, and has a linear relationship with flow discharge. All the rill flows tested are supercritical of Froude number greater than one. The influence of soil bulk density on the Froude number also varies with land slope, similar to that of flow velocity. The resistance coefficient in the range of 0.04-0.955 increases first and then decreases with the increasing slope or flow discharge, and its dependency on soil bulk density is significant, manifesting a decreasing trend in the case of mild or steep land slope.