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1.29%～8.18%。The frictional resistance of four kinds of samples with bionic concave-unsmooth surfaces and smooth surfaces were tested in moist soil at 35.1% moisture contents in the laboratory. Optimum theory was adopted to design experimental project. The results of the study revealed that normal load and speed had an effect on the frictional resistance. The experimental data was fitted to the mathematical models of frictional resistances. In the meantime, the interface variety of the bionics concave-unsmooth surface with soil was observed. The rates of resistance reduction of the bionics concave-unsmooth surface of the glass and plexiglass samples were 8.29%～24.65%, 1.29%～8.18% respectively under the condition of test.