In widespread multilevel statistical crystal plasticity models for describing the deformable polycrystalline materials behavior the spatial arrangement of structural elements (grains, subgrains) isn’t usually considered. At the same time for analyzing some physical mechanisms that have a significant effect on the polycrystals properties (for example, grain-boundary hardening, grain-boundary sliding, recrystallization, etc.), taking into account the mutual location of crystallites is critically important. In this regard, the authors have previously developed the statistical two-level elastic-viscoplastic model modification, which makes it possible to take into account this mutual arrangement. To implement this statistical model, information on a grain (subgrain) structure of investigated materials is required. The paper considers the procedure for describing the grain structure formation, based on using the polyhedra formed by the Laguerre method in a three-dimensional Euclidean space, with subsequent processing and transmission of the necessary data for setting a grain structure into the modified statistical model.