Six transition metal compounds [Cu(H2L)(CH3COO)]·H2O (1), [Cu(H2L)(CH3COO)] (2), [Cu(H2L)](ClO4)·CH3OH (3), 2[Cu(H2L)2] (4), [Co(H2L)2](NO3)·2CH3OH (5), and [Ni(H2L)](NO3) (6) were synthesized by reactions of the Schiff base ligand H3L (1‐{[2‐(2‐hydroxyethyl amino)ethylimino]methyl}naphthalen‐2‐ol) with the corresponding metal salts and characterized by single crystal X‐ray diffraction, elemental analysis, IR and UV/Vis spectroscopy and TG analysis. All compounds are mononuclear molecules, in which the Schiff base ligand exhibits diverse coordination modes and conformations. The N–H···O, O–H···O, and C–H···O inter‐ and intramolecular hydrogen bonding interactions link these molecules into multidimensional network supramolecular structures.