The asymmetric unit of the title compound, (C(6)H(4)S(4))(8)[Mo(6)O(19)](2)·CH(3)CN, contains two halves of two centrosymmetric [Mo(6)O(19)](2-) hexa-molybdate anions, which are each built up from six distorted MoO(6) octa-hedra sharing common edges and one common vertex at the central O atom, six tetra-thia-fulvalene cations (three of which are located on mirror planes) to balance the charge and a half of an acetonitrile solvent mol-ecule, likewise located on a mirror plane. The two central hexa-molybdate O atoms occupy special positions 2a and 2d, respectively. The cations and anions are inter-linked through C-H⋯O contacts.