Abstract: Field tests on a 50 m-high geogrid-reinforced soil embankment without concrete panel of Yichang-Badong Highway in Hubei Province are conducted. The tests include the measurements of tensile strain of geogrids, vertical earth pressure, horizontal earth pressure, layered settlement and deep horizontal displacement. The stress and deformation laws are revealed and the mechanism is analyzed. The results show that the maximum tensile strain of geogrids at different layers appears to be about 4-6 m away from the wrapped face, and the tensile strain along reinforcement has two peak values. The strain of geogrids has obvious lag in the construction period, it shrinks and rebounds after construction. The geogrids adjust the distribution of earth pressure. The measured value of the vertical earth pressure at the end of geogrids is slightly larger than the theoretical value, and it is less than the theoretical value in the middle and outside part of the slope. The horizontal earth pressure is nonlinear along the filled earth height. In the middle of the embankment, the horizontal earth pressure is larger than that at the top, and it is less than the active lateral earth pressure. There are a lot of volatilities in the layered settlement, and the value in the middle of the embankment is greater than that in other areas. The horizontal displacement decreases with depth, and it develops to a certain extent after construction.