The new layered title compound, barium di-μ-hydroxido-di-μ-vanadato-tricobaltate(II), was prepared under low-temperature hydrothermal conditions. Its crystal structure comprises Co2+ and O2− ions in the Kagomé geometry. The octahedral Co3O6(OH)2 Kagomé layers, made up of edge-shared CoO4(OH)2 octahedra with Co on a site of 2/m symmetry, alternate along the c axis with barium vanadate heteropolyhedral layers, in which Ba is on a site of inline imagem symmetry and V is on a site of 3m symmetry. All three O atoms and the H atom also occupy special positions: two O atoms and the H atom are on sites with 3m symmetry and one O atom is on a site with m symmetry. Ba[Co3(VO4)2(OH)2] represents the first compound from the four-component BaO–CoO–V2O5–H2O system and its structure is topologically related to the minerals vesignieite, Ba[Cu3(VO4)2(OH)2], and bayldonite, Pb[Cu3(AsO4)2(OH)2].