In this study, a facile co-electrodeposition method has been developed to co-deposit iridium oxide and human plasma proteins. We use a cyclic voltammetry (CV) approach for co-electrodeposition on indium tin oxide-coated glass substrates. We adjust the percentages of plasma proteins as 1%, 3%, 5% and 7% to obtain different film thicknesses. We also optimize the number of cycles to achieve the ideal thickness. Cyclic voltammetry, field emission scanning electron microscopy, and Fourier-transform infrared spectroscopy were used for characterizing the deposited film. The results show that the plasma proteins can be successfully co-deposited with iridium oxide. The incorporation of plasma proteins results in an increase in the roughness of the film. The thickness of the electrodeposited layer is dependent on the concentration of plasma proteins.