Graphical Abstract: Mixed-metal chain complexes constructed from lantern-type dinuclear ruthenium(II,III) carboxylate unit and tetracyanidonickelate(II), (PPh4)n[Ru2(O2CCH3)4Ni(CN)4]n•nH2O (1) and (PPh4)n[Ru2{O2CC(CH3)3}4]3n[Ni(CN)4]2n•2nH2O (2), where very weak antiferromagnetic interaction is operating, were synthesized and characterized by elemental analysis and IR and UV-vis spectroscopies and temperature dependence of magnetic susceptibilities (4.5—300K).