In this paper we present a study on the relation between the evolution, upon successive H(2) cycling, of the crystalline order and the H(2) sorption properties of Pd-capped textured Mg thin films grown on Si and glass substrates. Using an asymmetric diffraction geometry suitable for thin films, it is found that: i) hydrogen desorption can be achieved at low temperatures exposing the samples to air and ii) already upon one hydrogen absorption-desorption cycle, the original texture is lost. Moreover metal-to-insulator transition following magnesium hydride formation is observed through spectrophotometry. However, cycling results in being detrimental to film properties, mainly due to the Pd cap degradation and correlated processes. (C) 2009 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.