The invention provides a collection device of coal mine ventilation air methane. The collection device of the coal mine ventilation air methane comprises an air shaft diffusion tower, a wind collecting cover and an anti-explosion cover. The air shaft diffusion tower is of a tube body structure which is communicated from top to bottom. The wind collecting cover is a cover body which is communicated from top to bottom, the wind collecting cover is provided with an upper end opening and a lower end opening, and the lower end opening of the wind collecting cover covers the upper portion of the air shaft diffusion tower and is fixedly connected to the outside of the side wall of the air shaft diffusion tower. The anti-explosion cover is a cover body and covers the upper end opening of the wind collecting cover, a ventilation hole is formed in the side wall of the cover body of the wind collecting cover, and internal space of the tube body of the air shaft diffusion tower is communicated with the outside through the ventilation hole. By means of the device, the coal mine ventilation air methane can be effectively collected and conveyed, and a gas source is provided for follow-up use, for instance, gas in ventilation air methane flow is used as fuel for combustion-supporting and catalytic oxidation of a boiler and the ventilation air methane.