The utility model discloses a bar shape float valve with tongue holes for the air-liquid contact element in the plate type tower, which can be widely used for the mass transfer process, such as the distillation in the petroleum processing, the absorption, etc. The float vale is a long bar bench-shaped float valve composed of a valve surface and valve legs. The rectangular valve surface is provided with tongue holes with the same direction as the liquid flow. The tongue hole point is provided with tongue blades in inclined installation, so as to avoid the negative direction mixing and the liquid level fall of the liquid on the tower plate and eliminate the mass transfer dead area above the float valve. The two long edges of the valve surface of the float valve are bended downward, and the edge point is provide with a spacing nest slightly bending downward, which can avoid the fluctuation phenomenon that the valve surface is unstable in the rising and falling, and prevent the adhesion and the corrosion of the valve surface and the tower plate. The utility model is simple in structure and reasonable in design. Compared with the F1 type float valve tower disk and the tongue hole tower plate in the background technique, the bar shape float valve with tongue holes has the advantages of large operation elasticity and good separation effect. With the same separation requirement, the treating capacity can be improved by 20%, and the mass transfer efficiency is greatly improved.