n this study we report the development of copper ion sensor based on the electrochemical modification of a glassy carbon electrode by aurintricarboxylic acid ammonium salt (Aluminon). The deposited Aluminon layer was characterized by cyclic voltammetry and electrochemical impedance spectroscopy methods. The sensitivity of the developed ion sensor towards some metallic ions was evaluated by square-wave voltammetry. Among some tested metal ions the modified GC electrode shows a high and stable response towards the copper ions with a sensitivity of 23.8 μA·M–1 and detection limit around 3.16 10–7 M. In addition, UV-Visible spectrophotometry technique was carried out to confirm the best affinity between ATA and Cu2+ ions. An association constant of the host-guest complex of 20.104 L·mol–1 was obtained. As a result, a good selective copper ions sensor was obtained with low detection limit.