In order to solve the problem of increasing difficulty of water injection in deep coal seam and poor inhibition effect of emission，based on the theoretical method of wetting modification of coal seam，wetting agent was used to act on gas-bearing coal body to inhibit gas desorption and migration. The fluorocarbon FS-3100 surfactant with strong wettability was used to test the influence of wettability on the gas-water migration process in coal through gas-containing coal desorption test and fracturing fluid displacement flow test，and to explore the change mechanism of coal wettability on gas-containing coal desorption efficiency and flow capacity. The results show that the surface tension of water is reduced to 17.9 mN /m after adding wetting agent in water，and the contact angle of coal water is only 3-3.5°. After the wetting agent was used to modify the coal body，the desorption rate of gas in the coal is significantly reduced. The gas desorption rates of Xinjing and Baode coals are reduced to 46.08% and 39.2%，respectively，which are 8.4% and 9.8% higher than that of water. After the wetting agent acts on the coal body，the displacement flow rate of the Xinjing coal sample increases from 8.59% to 14.10%，and the Baode coal sample increases from 10.65% to 16.67%，and the water injection capacity of the coal body is significantly enhanced. The wetting agent molecules are adsorbed on the surface of the coal matrix，which reduces the interfacial tension between coal and water and the surface energy of the coal body，so that the friction resistance of the water molecules flowing in the pores and fissures of the coal body is reduced，and the water molecules can infiltrate smaller-scale pores and produce stronger water lock effect. Finally，the gas desorption and migration adsorbed on the pores and coal surface are inhibited，and the gas plugging effect is formed.