Abstract: A portable and nondestructive adhesive tape corrosion sensor which is utilized under actual field or laboratory conditions in detecting coating and substrate degradation using Electrochemical Impedance Spectroscopy (EIS) of coated or uncoated metal structures has been developed. The invention allows for broad applicability, flexibility in utilizing the sensor in various environments without structural compromise and the ability to inspect and evaluate corrosion of the actual structure, regardless of the size, shape, composition, or orientation of the structure. The electrodes may be removed once a measurement is made or remain in the original fixed position so that subsequent measurements may be made with the same electrode. The nondestructive sensor apparatus is comprised of a pressure-sensitive adhesive tape that consists of a conductive film or foil and conductive adhesive overlapping another pressure-sensitive adhesive tape that consists of a conductive film or foil and non-conductive adhesive.