New Ba5(V2O7)2Cl2 was isolated by a high-temp. (850°) reaction employing a CsCl/RbCl flux. The structure was detd. by single crystal x-ray diffraction methods. This compd. crystallizes in an orthorhombic crystal system, space group Pmmn, with a 11.558(2), b 15.164(3), c 10.023(2) Å, Z = 4. The structure of Ba5(V2O7)2Cl2 was detd. by full-matrix, least-squares methods with R1 = 0.0398, wR2 = 0.1069 and GOF = 1.048 for all data. Crystallog. data are given. This new structure can be described as a composite lattice made up of mixed covalent and ionic moieties. The extended framework is orchestrated by stacked [Ba(V2O7)Cl]3- slabs that are interconnected by Ba2+ cations through Ba-O bonds to the [V2O7] units. The Ba2+ and Cl- ions form BN-type [BaCl] sheets with pseudo-hexagonal windows that are centered by [V2O7]4- pyrovanadate units.