Two new ligands, 1,2‐propylimino‐bis(isonitroso‐2‐acetylnaphthalene) (H2L1) and 1,2‐ethyl‐imino‐bis(isonitroso‐2‐acetylnaphthalene) (H2L2), have been synthesized by the reaction of isonitroso‐2‐acetylnaphthalene with 1,2‐diaminopropane or 1,2‐diamino‐ethane. These ligands were reacted with nickel(II), copper(II), cobalt(II), zinc(II), cadmium(II) and mercury(II) ions to form complexes containing tetradentate Schiff bases. Each metal ion is in a four‐coordinate environment of two imine nitrogen atoms and two oxime oxygen atoms. The new compounds have been characterized by elemental analyses, magnetic susceptibility, mass, IR, 1H and 13C NMR spectroscopy.