The new oxysulfide Ba10V6S7O18, that can be written as Ba10S(VO3S)6, was prepared by solid state reaction. It crystallizes in the non-centrosymmetric P63 space group with the unit cell parameters a=18.3018(2) Å and c=8.6525(2) Å, R1 = 3.21%. This original phase exhibits (VO3S) units separated by Ba 2+ cations, the later delimit 1D-hexagonal-like cavities filled by disordered sulfur S 2anions and arranged into two kinds of sulfur-deficient 1D-channels. DFT calculations were employed to get insights into the chemical bonding and parameters ruling the structure, particularly the V-O vs. V-S bonding inside the mixed anion VO3S tetrahedra, and the contribution of the S 2of the cavities. The title compound can be decomposed with three components mainly interacting by ionic bonds as follows, Ba10V6S7O18 → [Ba10] 20+ [S] 2-[(VO3S)6] 18-, this description may pave the way to the design of other phases related to this system with adjusted band gap features. In particular, the effect of the V(O,S)4/Ba ratio is discussed to emphasize the presence of the [S] 2component, in comparison with related structures such as Ba6V4O5S11 [Ba6(VO2S2)2(VS3O)(VS4)], as it contributes strongly just below the fermi level with subsequent alteration of the band gap.