In the title compound, {[Mn(C(14)H(14)N(4))(2)(H(2)O)(2)](NO(3))(2)}(n), the Mn(II) ion is located on an inversion center and is coordinated by four N atoms from four 1,3-bis-(1H-imidazol-1-ylmeth-yl)benzene (L) ligands and two water mol-ecules in a distorted octa-hedral geometry. Two L ligands are related by a centre of symmetry and bridge Mn(II) ions, forming a positively charged polymeric chain in [101]. Uncoordinated nitrate anions further link these chains into layers parallel to the ac plane via O-H⋯O hydrogen bonds.