In the framework of density functional theory, the structural, lattice dynamical and thermodynamical properties of the C15-type of Al2Ca and Al2Mg compounds are investigated. The calculated lattice constants are in good agreement with the other works. The results show that these compounds are dynamically stable in the considered structure. The temperature dependence of the various thermodynamical quantities such as internal energy, free energy, entropy, and heat capacity are also predicted within the harmonic approximation, and the observed trends are discussed in detail. (C) 2012 Elsevier B.V. All rights reserved.