The bulk and surface electronic structure of SnSb2Te4 and PbSb2Te4 ternary compounds consisting of three septuple layer blocks separated by van der Waals gaps has been theoretically studied. It has been shown these systems are three dimensional topological insulators. The calculations of the MSb2Te4 (M = Pb, Sn) surface electronic structure show that these compound are well promising for practical application compared to parent Sb2Te3 compound. (C) 2012 Elsevier B. V. All rights reserved.