In Woreta-Debre Tabor road section part of Woreta-Woldia link road there is around 400 m section of the road which is un-surfaced from construction period up to know due to instability problems happened during construction and extended up to know without a solution. This paper focus on the assessment of geotechnical material properties in sub base and subgrade of the failed road section by using soil samples taken from seven test pits transversally coincide with the apex of actively failed slope section at river bank and analyzed for engineering properties: water content, specific gravity, density, particle size distribution, California Bearing Ratio, shear strength parameters, permeability, and Atterberg limit tests as per ASTM standards. And also numerically investigate with finite difference software package to determine factor of safety for the failed road section without and with mitigation measures to recommend appropriate solution for the problem. According to the results, the soil in the study area is fine, gap graded, semi-solid state, medium to highly plastic, some to heavily over-consolidated, very soft to medium, and practically semi pervious to impervious. Software results indicate factor of safety is greater than one in dry, saturated, saturated traffic, and when groundwater within one meter from river bed, but when groundwater rise to the surface the road becomes unstable with factor of safety less than one which decreases gradually with increase in groundwater depth and finally the soil collapses. According to this research finding, the road in the study area is unstable due to groundwater, which rises to the surface of the road and generates springs at upstream of the failed road during rainy season. The road becomes stable when groundwater lowers twenty two meter from road surface or using retaining walls for soil properties in model one and two. Keywords: slope stability, geotechnical conditions, factor of safety, groundwater.