Dissymmetric bis-quaternary ammonium with imidazoline ring was evaluated for corrosion inhibition efficiency against Q235 steel in 1.0mol•L-1hydrochloric acid solution at room temperature (298K) by gravimetric method, potentiodynamic polarization, electrochemical impedance spect- rum(EIS) and quantum chemical calculation. The results of mass loss and polarization data showed the compound acted as a very good mix-up inhibitor for Q235 steel in 1.0mol•L-1hydrochloric acid solution. EIS results showed that the associated values of the charge transfer resistance (Rct) increase by increasing the additive concentrations and immersing time whereas the associated values of double layer capacitance (Cdl) decrease. These changes in the impedance parameters (Rct and Cdl) are indicative of adsorption of the compound on Q235 steel surface leading to the formation of a protective film. The obtained correlations and Quantum chemical calculations conclusions agree well with the experimental results.