The effect of the chemical structure of metal-organic framework compounds (MOF) (the presence of coordination-unsaturated metal ions, the nature of the metal ions, the presence of electron donor and electron acceptor groups in the ligands) on the ability of such compounds to sorb hydrogen is examined. It is shown that the macroscopic parameters (the surface area and pore size) make a major contribution to the adsorption of hydrogen while the chemical structure of the MOF plays a subsidiary role by determining the structural characteristics of the adsorbent.Key words: metal-organic frameworks, porous coordination polymers, hydrogen sorption, coordination-unsaturated ions, effect of the nature of metal ions, effect of functional groups.