Abstract: Rainfall-infiltration processes under artificial Robinia pseudoacacia plantation and afforestation technology in the slope of low-land in Taihang Mountains were studied.The results show that the water potential in 10～30cm soil section quickly increases to maximum with rainfall and decreases gradually after rainfall stops.With infiltration,the wetting peak gradually moves ahead.Curve of water potential changes from steep to slow.Comprising the water potential variation in different vegetations,infiltration velocity is slower in forest land than that in naked land at the beginning of rainfall.With rainfall going on,the speed of wetting peak moving ahead in forest land is quicker than that in naked land.Litters and vegetations slow down the lateral and subsurface flow and increase the one- dimensional vertical infiltration.