Schwarzites are one of the most well-known forms of nanoporous carbon. High porosity and large surface area of these materials make them promising candidates for molecular hydrogen storage. Quantum-chemical modeling showed that hydrogen weight fraction inside D-schwarzite structure depends on the number of atoms per unit cell that determines its size and morphology. D480 schwarzite has demonstrated the largest value of hydrogen sorption capacity amongst the structures considered in this work. It reaches 7.65% at the technologically acceptable values of temperature and pressure (300 K and 10MP alpha.). Though being lower than that required by DOE (9%), this amount can be increased by using schwarzites with larger unit cell corresponding to the larger surface area. (C) 2017 Elsevier B.V. All rights reserved.