Hydrogen adsorption on PdGa intermetallic compound is analyzed using density functional theory (OFT) calculations. Changes in the electronic structure of PdGa(100), (111) and ((1) over bar(1) over bar(1) over bar) surfaces and H bonding after adsorption are addressed. H interacts with Pd atoms with a tilted geometry on (100) and (111) surfaces. On the ((1) over bar(1) over bar(1) over bar) surface two possible forms for H adsorption are detected: one is observed atop perpendicular to the surface and the other one is subsuperficial, both with similar adsorption energies. The Ga-H interaction is energetically less stable and is only present on the (100) plane. Pd-Pd bond strength decreases up to 53.8% as the new Pd-H bond is formed. The Pd-H bond length differs less than 1%, compared to the gas phase value for the (100), ((1) over bar(1) over bar(1) over bar) and atop However in the ((1) over bar(1) over bar(1) over bar) subsurface-H bond length is about 2.17 angstrom. The effect of H is limited to its first Pd neighbor. Analysis of orbital interaction reveals that the Pd-H bond mainly involves s-s and s-p orbitals with lower participation of Pd 4d orbitals. The computed H vibration frequencies after adsorption show values of 1786, 1289 and 633.5 cm(-1) that correspond to top, bridge and hollow sites respectively. Copyright (C) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.