Corn stem flow is the amount of water flowing along the stalk to the root after intercepted by the corn canopy during rainfall. It is an important component of surface runoff on the slope and has an important effect on the soil erosion process at the root of the plant. In this paper, artificial rainfall simulation method was used to study the effect of corn stem flow on soil erosion in sloping field. The test soil trough was 0.40 m long, 0.23 m wide, and 0.14 m deep. A PVC pipe with a diameter of 2 cm was used to simulate the corn stalk at the maturity stage and the height was 1.2 m. The simulated stem flow was 5, 10 and 15 g/s, with the same rainfall under the conditions, the stalk-free sloping land was used as a control measure. The rainfall intensity was 60, 90, 120 mm/h, the rainfall lasted 108 minutes, and the slope was 10°. The results showed that: (1) Compared with the control measures, the stem flow has the effect of accelerating sloping surface runoff. (2) The surface runoff and sediment yield under simulated stem flow were higher than the control, compared with no stem flow slope, under three rainfall intensities, the contribution rate of runoff from the three stems was 14.90%~43.10%, and the contribution rate of sand production was between 12.47% and 26.75%. (3) The stem flow formed a small surface around the stem, and the currents caused the soil erosion process to change from surface erosion to gully erosion, thereby increased the slope soil erosion amout. Therefore, the soil erosion of stem flow should be considered in the calculation and evaluation of soil erosion on slope farmland.