After two years' experiment in the west loess hilly and gully region with serious soil erosion,the effects of various tillage ways on soil water characteristics and soil erosion in slope farmland were studied. Results showed that (1) No-tillage with straw covering had good water conservation effect and its mean soil water content in a year was 1% higher than traditional tillage. There was no obvious difference between the no-tillage and traditional tillage. (2) Soil water content in cultivated layer kept steadily in the no-tillage,which benefits seedling emergence in early spring and crop growth after rainfall. (3) The effects of various tillage ways on soil water characteristics were related to the change of soil structure. Soil bulk density was increased by the no-tillage,the destruction ratio of soil aggregates was reduced,and the anti-erosion ability of soil was increased by the increment of the stability. Straw covering reduced soil bulk density and enhanced soil water retaining capacity. (4) The no-tillage might not reduce runoff on farmland,but it obviously controlled soil erosion. No-tillage with straw covering controlled soil and water loss efficiently and runoff and soil erosion were reduced by 8.35% and 88.11%,respectively.