In this study, Mg2-xMxAl4Si5O18, where M=Fe and x=0.0, 0.20, 0.50,1.0 and 1.5, have been synthesized using an arc-melter system. As a result of Fe-substitution, complex, deformed and multiphase samples were obtained. Microstructural analysis indicated that crystals of alpha-cordierite disappeared in the x=1.5 Fe-substituted sample. However, more densified samples than the unsubstituted sample were obtained. Dielectric constant increased gradually and capacitive resistance decreased with increasing the Fe-content in the system. The results suggested that the Mg2Al4Si5O18 materials obtained by the Fe-substitution are not suitable for high frequency applications. (C) 2014 Elsevier B.V. All rights reserved.