Organic-inorganic hybrid materials are an upcoming class of materials that attract increasing research interest. In the present manuscript, we report on the combination of a particularly versatile organic matrix – the conductive polymer polyaniline (PAni) – with a special type of polyoxometalates (POMs), namely a lacunary Keggin anion, [AsW9O33]9–. Although the high application potential and the manifold structural motifs of POMs provide an almost infinite number of options for composite materials, up to now, only few POM-polymer combinations have been explored in more detail. Thus, we have investigated the interaction of PAni with the unique reactivity of [AsW9O33]9– that combines building-block facilities with the presence of a lone pair on the heteroatom. The resulting composite material was characterized with a wide spectrum of analytical techniques and the effect on the reaction conditions on the nanoscale structuring was investigated. Furthermore, the newly synthesized POM-PAni composites display a stable temperature-dependent resistivity that renders them promising for further applications.