AstroMD is a visualization software offering several capabilities specifically oriented to the cosmological analysis of three-dimensional structures. It was developed within the framework of the Cosmo.Lab project, financially supported by the European Community, which involves several European Astrophysical Institutions and the CINECA. This tool gives a 3D graphic representation of data, exploiting the most advanced visualization technology based on virtual reality, and has several built-in-tools which allow the user an efficient manipulation and analysis of data, in order to build a leading edge instrument for scientific research. It was developed using the Visualization Toolkit (VTK) by Kitware, a freely available visualization library portable on many platforms. AstroMD is an open source freely available code at the address http://cosmolab.cineca.it/.