The question of fullerite C-60 hydrogenation is the subject of this paper. Notice that hydrogen in fullerite can be in two states: lattice and fullerinated. The calculation of hydrogen content in the lattice of fullerite in the form of solid solution has been carried out. The structure of C60 molecule has been considered. Processes of transformation of C60 molecule and fcc lattice of fullerite with the formation of stable hydrogenated phases C60H6, C60H18, C60H36, C60H48 and C60H60 has been discussed. The lattice destruction of fullerite C-60 at hydrogenation has been explained. The limiting concentration of hydrogen in fullerite at a level of about 5 mass% has been justified. (C) 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.