Two cyano-bridged Ni(II)−Fe(III) complexes {(H3O)Ni(H2L)2Fe(CN)62·Fe(CN)6·6H2O} n (1 ) and K(18-C-6)(H2O)2Ni(H2L)2Fe(CN)63·4(18-C-6)·20H2O (2 ) (L = 3,10-bis(2-aminoethyl)-1,3,6,8,10,12-hexaazacyclotetradecane, 18-C-6 = 18-crown-6-ether) have been synthesized and characterized structurally and magnetically. Complex 1 has a zigzag one-dimensional structure, in which two trans-CN- ligands of each Fe(CN)63- link two trans-Ni(H2L)4+ groups, and in turn, each trans-Ni(H2L)4+ links two Fe(CN)63- in a trans fashion. Complex 2 is composed of cyano-bridged pentanuclear molecules with moieties connected by the trans-CN- ligands of Fe(CN)63-. Magnetic studies show the existence of ferromagnetic Ni(II)−Fe(III) interactions in both complexes. The intermetallic magnetic coupling constant of both complexes was analyzed by using an approximate model on the basis of the structural features.