A Schiff base complex of the coper was prepared [tetrakis (μ3-2-{[1, 1-bis (hydroxymethyl)-2-oxidoethyl]imino-methyl}-phenolato)tetrakis[aquacopper(II)]] that referred as complex A then it characterized by FTIR, UV and NMR techniques. The prepared complex is evaluated as corrosion inhibitor for carbon steel alloy (C1010) in corrosive medium of 0.1M HCl at 25ºC at different concentrations i.e., (10-50) ppm. An optimal concentration is 10 ppm which gives efficiency about 52%. In order to raise the efficiency of the mentioned inhibitor, 7ppm of potassium iodide (KI) is added to the inhibitor, where the efficiency of the certain inhibitor raised its efficiency into high significant values for all concentrations of the inhibitor. The results insisted that the optimal efficiency is 88% at 40 ppm. On other hand, the effect of the temperature on the inhibition efficiency for the inhibitor when it mixed with KI is studied temperatures range of (25-55) ºC for all concentrations and the results reveals that the efficiency is reduced as temperature increased. Furthermore, the kinetic and thermodynamic functions were calculated and the results reveal that the inhibitor is physically adsorbed and obey to the Langmuir adsorption isotherm.