The bearing capacity of piles on the ground is one of the main characteristics of pile foundations, which is responsible for its interaction with the ground. This characteristic depends on many factors: the granulometric composition of the soil, its moisture content, con-sistency, texture, as well as the type and properties of the pile material. One of the main charac-teristics of the pile material is its surface roughness. In many studies, the dependence of the angle of friction of the soil against the material of the pile on the value of the roughness of its surface was noted. At the same time, all studies focused exclusively on the dependence of the angle of friction on the roughness, not paying attention to the possibility of its variability in the process of driving the pile into the ground. This goal was set in the framework of this study. Using a standard single-plane cutter, the passage of a composite pile at a distance of 0.5m was simulated at a depth of 10 m. Before and after the test, the surface roughness parameters were measured using the Seitronic PSh8-1 SS device. The results showed that after the test, the roughness of the fiberglass plate made on the basis of polyester resin by the pultrusion method decreased by 44.4%.