A gas-liquid separation device in which gas passes through a wire mesh pad of a demister to remove entrained mist. It is usually composed of a gas-liquid filter mat and a support member. The net block is composed of a plurality of tiled wave-shaped screens and grid, positioning rods atc. The wire mesh demister is a wire-weaved, tightly separated layer of a certain thickness that is horizontally mounted in a container for removing liquid impurities from the gas. The demister works on the basis of a large amount of particulate matter intercepting entrained droplets in the vapor stream. When the gaseous vapor flows vertically through the separation layer, the liquid impurities are removed. It is not recommended to use a demister to handle dirty media, which may cause blockage and reduce separation efficiency.