The structural and magnetic properties of MnNb2-xVxO6 samples were studied. These materials belong to the AB(2)O(6) class, which presents low-dimensional magnetism. Curie-Weiss fitting gives a negative Weiss temperature that is a characteristic of dominant antiferromagnetic interactions in paramagnetic region. Rietveld refinements of neutron diffraction data show that magnetic moments are aligned antiferromagnetically within the zig-zag chains running along the c axis. Unlike other ANb(2)O(6) type systems crystallizing also in Pbcn space group and presenting ferromagnetic Ising chains, MnNb2-xVxO6 samples exhibit antiferromagnetic type order along the chains. At 1.5 K, the Mn atoms are found to carry an ordered magnetic moment of about 4.3 mu(B). The Mn chains are antiferromagnetic and do not present significant anisotropy. These characteristics and the high spin allowed us to model the system as weakly interacting classical Heisenberg chains, estimating the values of both intra- and interchain exchange constants evolution with x content. (C) 2015 Elsevier Ltd. All rights reserved.