In the given scientific publication, calculations of 3D parameter Vm (material volume) of surfaces with irregular roughness and comparison with experimental data were performed, with further application of this parameter in calculations of wear intensity. First, using Mountains Map software for profilometric measurements, 3D roughness processing and determination of material volume Vm at specific relative levels γ were performed. The next step was an additional analysis of the distribution of surface ordinates using a theoretical and experimental Laplace function. The given check confirmed that for mostly surfaces with irregular roughness the ordinates’ distribution corresponds to the Normal Gaussian distribution law, but in cases when the asymmetry of the ordinates’ distribution function goes outside the permissible limits (|∆Ssk|> 10%), errors> 10% occur. On this basis, the mathematical formula of the material volume Vm was derived, and the obtained calculations were compared with the measured values. The results showed that the calculated values of the parameter Vm are very close to the experimental data (|∆Vm| <10%), while at the relative level γ=+3, errors occur, what is related with the deviation from the Normal distribution law. It was concluded that the given parameter can be used in the calculations of linear wear intensity, knowing the relative level γ.