Mg(BH4)(2)center dot(NE3)(2) (NH3BH3) is an important H-enriched hydrogen storage material capable of releasing high-purity hydrogen. This work investigated the elastic and electronic properties of mgMg(BH4)(2)center dot(NE3)(2) (NH3BH3) using first-principle calculations for the elastic constants, bulk modulus, Young's modulus, B/G. Results show this compound is mechanically stable and classified as a brittle material. Three-dimensional curves indicate significant anisotropy exists in the (010) and (100) planes for bulk modulus and the (001) plane for Young's modulus. The (001) plane elastic anisotropy is larger than those of the (010) and (0(-)1 0) planes. An electronic properties analysis indicates this compound is a semiconductor with a 1.151 eV band gap. There exist the strong B-H, Mg-N interactions from the analysis of density of state, which are further confirmed by Bader's quantum theory of atoms in molecules (QTAIM). (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.