Abstract: Efficient air filter element is a key component to prevent erosion, corrosion and solids precipitation in the flow path of gas turbine. However, the performance of the air filter element is significantly reduced in high humidity environment, which seriously affects the safe operation of gas turbine. Herein, the filtration performance of four types of filter element made of F9 filter materials was tested. By comparing the tensile strength of the filter materials under different conditions, the change of pressure drop and efficiency of the filter element was measured in the conditions with different droplet mass concentration. The results show that the moisture resistance of the filter material mainly depends on the fiber composition. The synthetic fiber can effectively reduce the water absorption rate of the filter materials, and the filter element made of materials with low water absorption rate has a stronger capability to maintain its original performance with the influence of water spray. The research results could provide technical reference for the operation and maintenance of gas turbine inlet filtration system and the development of efficient moisture-resistant filter elements.