Vegetation is one of the key factors affecting soil erosion in semi-arid environments. The evaluation of the influence of Sainfoin on soil erosion can provide important information about soil and water conservation. In this study, the effects of vegetation destruction and vegetation restoration on soil erosion were quantified using data from field runoff plots established in a semi-arid zone in Northeastern Turkey. This study was performed between 2005 (June) and 2009 (January). The experimental design at the site included a randomized complete block with four replicates (a total of 12 experimental plots: 3 treatments x 4 replicates). Each plot was 20-m long x 5-m wide, which is Wide enough to minimize edge effects and large enough for downslope rills to develop. The control plot (A) was maintained, bare of vegetation by manual removal of the plant cover and, regular herbicide treatments. In the second plot (B), Sainfoin was seeded in 25 cm wide and 60 cm long rows, at a density of 8.5 g of seeds per square meter in October, 2005 after clearing the existing vegetation. The third plot contained natural vegetation shrub (Paliurus spina-christi Mill.) and perennial grass (Cynodon dactylon L., Achillea sp., Astragalus sp.) vegetation (C) that maintained at an approximately 63% coverage (October, 2005) of the soil surface.