The oil-water separation filter element is mainly designed for oil-water-liquid separation. It contains two kinds of filter elements, namely: coalescence filter element and separation filter element. For example, in the oil dewatering system, after the oil flows into the coalescing separator, it first flows through the coalescing filter element, which filters out solid impurities, and coalesces extremely small water droplets into larger water droplets. Most of the coalesced water droplets can be separated and removed from the oil by their own weight and settled in the water collection tank.