Abstract: A ceramic bodied sensor having helical metallized electrodes for measuring the capacitance of an oil-water-gas or oil-water mixture flowing through a central bore of the sensor is disclosed. The sensor generally is a hollow cylinder with an inner ceramic layer which is very thin, a thicker outer ceramic layer which forms a strong structural unit, and a pair of isolated metallized electrodes which are generally approximately located between the inner and outer ceramic layers. The inner ceramic layer, outer ceramic layer and metallized electrodes form a dense monolithic ceramic tube. The electrode plates are preferably identical in size and shape and are isolated from one another electrically so that a condenser is formed by the separated plates. The inner ceramic layer is preferably very thin to minimize its capacitance value in comparison to the capacitance value of the water-oil-gas or oil-water mixture flowing through the central bore of the sensor.