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Two new coordination polymers (CPs) based on Zn(II) and Cd(II) and 1<i>H-</i>indazole-6-carboxylic acid (H₂L) of general formulae [Zn(L)(H₂O)]_n (<b>1</b>) and [Cd₂(HL)₄]_n (<b>2</b>) have been synthesized and fully characterized by elemental analyses, Fourier transformed infrared spectroscopy and single crystal X-ray diffraction. The results indicate that compound <b>1</b> possesses double chains in its structure whereas <b>2</b> exhibits a 3D network. The intermolecular interactions, including hydrogen bonds, C–H···π and π···π stacking interactions, stabilize both crystal structures. Photoluminescence (PL) properties have shown that compounds <b>1</b> and <b>2</b> present similar emission spectra compared to the free-ligand. The emission spectra are also studied from the theoretical point of view by means of time-dependent density-functional theory (TD-DFT) calculations to confirm that ligand-centred <i>π-π*</i> electronic transitions govern emission of compound <b>1</b> and <b>2</b>. Finally, the PL properties are also studied in aqueous solution to explore the stability and emission capacity of the compounds.