Two cobalt(II) and cadmium(II) complexes, [Co(H2DMOPhIDC)2(H2O)2] • 2H2O (H3DMOPhIDC = 2-(3,4-dimethoxyphenyl)-1H-imidazole-4,5-dicarboxylic acid) (I), [Cd(H2MOPhIDC)2-(Phen)] • C2H5OH (H3MOPhIDC = 2-(3-dimethoxyphenyl)-1H-imidazole-4,5-dicarboxylic acid, Phen = 1,10-phenanthroline) (II), have been hydro(solvo)thermally synthesized by employing two kinds of organic ligands, H3DMOPhIDC or H3MOPhIDC, respectively. The molecular structures of I and II have been characterized by IR spectra, elemental analyses and single-crystal X-ray diffraction (CIF files CCDC nos. 935845 (I), 935846 (II)). Both complexes show three-dimensional supramolecular structures supported by intermolecular H-bonds. Furthermore, the thermogravimetric and photoluminescent properties of two complexes have been investigated as well.