Abstract <p>A racemic helical Schiff base (H₄<b>L</b>) incorporating both pyridine-2,6-dicarboxamide and β-ketoimine units was designed and synthesized from the reaction of precursors <i>N</i>,<i>N</i>′-bis(2-aminophenyl)-pyridine-2,6-dicarboxamide and 1,1-phenylbutane-1,3-dione. Its structure was characterized by ¹H NMR, ¹³C NMR, infrared spectra, elemental analysis, and single-crystal X-ray diffraction. The ion recognition property of H₄<b>L</b> toward a series of metal ions was investigated using UV–Vis absorption spectra, which showed that H₄<b>L</b> displayed a selective recognition of Cu²⁺ ions over other metal ions in methanol. The binding ratio, association constant, and the limit of detection were estimated. Moreover, the crystal structure of the Cu(II) complex ([Cu₂(<b>L</b>^4–)H₂O]‧CH₃OH) obtained from the coordination reaction of H₄<b>L</b> with Cu²⁺ ions well accounted for the binding mode of H₄<b>L</b> with Cu²⁺ ions in the solution.</p>