The invention discloses a gas desulfurization tank. The gas desulfurization tank comprises a tank body, the tank body is provided with an air inlet at the lower part of the tank body and a gas outlet at the upper part of the tank body, an agent delivery pipe for conveying a desulfurizer is arranged in the wall of the tank, the agent delivery pipe is communicated with a delivery pipe outside the tank, the tail end of the delivery pipe is provided with a fan, a desulfurizer basin is arranged above the middle of the delivery pipe, the middle of the delivery pipe is communicated with the desulfurizer basin through an agent distribution multistage pipe, M horizontal hollow powder filter screens are arranged in the tank, M represents a natural number greater than or equal to 1, the hollow powder filter screen comprises N layers of parallel filter screen cakes, N represents a natural number greater than or equal to 2, the filter screen cakes are fixedly connected to the wall of the tank and are communicated with the agent delivery pipe, the filter screen cakes are in a shape of round cakes, a round cake-shaped cavity is arranged in each one of the filter screen cakes and the filter screen cake is surrounded and enclosed through chemical fiber netty gauze. The invention provides the gas desulfurization tank with good desulfurization effects.