The research is devoted to the elaboration of the wear part contact estimation using 3D sur-face texture parameters defined in the standard ISO 25178-2:2012 for contact (it is known that elastic contact gives less wear rate) area, friction, and wear rate determination. In our research, the sphere and random flat surface model was used, where the height of surface asperities h(x, y) had a normal probability distribution. As a result of research, the equations for estimation of the elastic contact area were derived and, we obtained conditions at which it was possible to use equations for flat random surfaces. The results of this study could have wide practical application, for example, in design, choosing the geometrical and physical-mechanical param-eters of the parts, calculation of real stresses, wear rate and life time of contact parts, etc