A simple colorimetric acetate ion receptor based on 3-methoxysalicylaldehyde-4′-nitrophenyl-hydrazone was synthesized in an ethanol solution through one step,and characterized by 1H NMR and elemental analyses.Its anion-binding ability was examined by UV-Vis absorption spectroscopy in DMSO(dimethyl sulfoxide).The result shows that the compound has a high affinity for and a high selectivity toward acetate ions,and also an advantage of ‘naked-eye' recognition of color changing from yellow to purple.