Abstract：The seepage of water is relatively simple within saturated soils. However，the temporal and spatial distributions of seepage speed and direction are more complicated in unsaturated soils，which are needed to be determined for calculating the settlement of loess with water increasing or reducing. This paper addresses these problems through in-situ testing study on infiltration in unsaturated loess. The results show that，at the stage of unsaturated infiltration，the saturation degree varies approximately linear with the time at different depths，and the time of infiltrating within shallow layers is also approximately linear related to the depth for a short period. In addition，the soggy angle of loess is found to be slightly larger than 30°.
