The ways that roadside earth disposal give off sediments include rill erosion, inter-rill erosion and slumping. This study is focused on soil erosion on the road dumps. Erosion pins method was adopted to observe the erosion processes in 5 disposal sites. Another small plot was selected to collect runoff and sediments. Automatic device was installed for continuous rainfall and runoff recordings. Analysis of data reveals that both effective runoff and erosion rate decrease with increasing age of road dumps, and might be attributed to vegetation growth.