The method of productivity increase of production processes of polycrystalline silicon by hydrogen reduction at the expense of increase of a surface of initial cores-bases is considered. It is shown that the productivity gain is possible at use of cores-bases with the sizes which are in a certain interval, and the maximum gain will be at use of cores of the optimum cross-section sizes (diameter). Analytical formula for a finding of optimum value of diameter depending on equipment characteristics is received. As a result of the analysis characteristics and the parameters of the process most influencing efficiency of the considered method are revealed.