<p>Herein, synthesis, characterization and metal ion sensing of naphthalene linked 1,2,3-triazole chemosensor (<b>5</b>) synthesized by CuAAC approach is reported. The new molecule yielded a unique molecular architecture with potential applications as Fe²⁺ and Fe³⁺ ions sensor using fluorescence spectroscopy as well as naked eye detection. Ion sensing experiments revealed that, a prominent selective sensing of Fe²⁺ over Fe³⁺ ions by probe <b>5</b> without any interference from other cations was observed with 1:1 binding ratio for both probe <b>5</b>-Fe²⁺ and probe <b>5</b>-Fe³⁺ ions as determined by Job’s plot method. The Limit of Detection (LOD) was calculated to be 82 nM and 1.8 nM for Fe²⁺ and Fe³⁺ ions, respectively. The DFT calculations were executed using B3LYP/6-311G++(d, p) for free probe and B3LYP/LANL2DZ for the associated metal complexes to elucidate binding interactions, confirming the metal-ligand interactions. The combined experimental and theoretical results provide an accurate detection framework for Fe²⁺/Fe³⁺ metal ions in environmental and biological samples.</p>