According to the information obtained from the bionics study on soil animals,the aspects of gemometrical shapes and flexibility can be applied to the bionics analogy. The objective functions and their constraint equations for digital optimization of bionics flexible unsmoothed surfaces were established on the basis of bionics analogy.The dimensions of various structure units of the bionics flexible unsmoothed surface were obtained. Based on the CAD gemometric modelling, the arrangement and link of the structure units were determined and then the bionics flexible unsmoothed surfaces of the shape of cylinder,semicylinder, cloth, chain were obtained. It created a condition to develop the bionics flexible unsmoothed technology of decreasing adhesion and reducing resistance.