In the present study, CdSe Nanoparticles (CdSe-NPs) were characterized using UV-vis (ultraviolet) and TEM (transmission electron microscope) and added to nonionic surfactant (NS) with different ratios (1, 2, 3 and 4 wt%) of to formulate CdSe-NS nanocomposite for caron steel (CS) corrosion control. The inhibition effect of the prepared inhibitor was investigated via electrochemical techniques such as electrochemical impedance spectroscopy (EIS) and potentiodynaminc polarization (PDP) besides weight loss measurements. The data obtained from EIS showed that, the addition of CdSe-NPs enhanced the inhibition efficacy of the prepared inhibitor till reach 96.55% at 4%wt-CdSe-NS compared with that value at 0%wt-CdSe-NS was 91.59% which indicated the role of CdSe-NPs in CS protection. While, PDP showed that the prepared inhibitors acted as mixed-type inhibitors. The corresponding dielectric functions (DF) are discussed in the light of the optoelectrical parameters and dispersion parameters. The strong sorption ability of CdSe-NS, resulting in the creation of a monolayer, which isolate CS surface from the corrosive environment and hence reduces its attack through the absorption process as well. Also, Atomic Force Microscope (AFM) was applied for more information about CS surface morphology.