A coupled multielectrode array sensor (CMAS) with fingered electrodes for monitoring corrosion in oil-water mixtures and gas systems containing hydrogen sulphide was described. Except for the sensing areas at the tip sections all surfaces of the fingered electrodes are coated with an inner electrically insulating coating and an outer ion conducting coating. The electrodes are spaced such that there are gaps between the outer coating surfaces of the neighbouring electrodes to prevent the formation of a continuously distributed electron conducting deposits between the sensing surface of one electrode and the sensing surfaces of the other electrodes. The ion conducting coating maintains the ionic conducting path among the multiple electrodes’ sensing areas in non-continuous electrolyte. These probes are especially designed for applications in gas systems and oil-water mixtures containing hydrogen sulphide that often led the formation of electron conducting deposits on the commonly used corrosion probes [such as electrical resistance (ER) and linear polarization resistance (LPR) probes].