Air Filter Device

An air filter device includes an air filter and a filter case having a filter housing for housing the air filter. The filter case has a pipe part enclosing an outer circumference of a second end of a filler pipe. The second end of the filler pipe defines a fuel filler opening and is opposite to a first end of the filler pipe connected to a fuel tank of a vehicle. A distance between the pipe part and the fuel filler opening is less than a distance between the filter housing and the fuel filler opening. The pipe part is configured to be inserted into a fixed member fixed to a vehicle body. The pipe part has a flange that extends radially outward from the pipe part and is spaced apart from the filter housing in an axial direction.