Abstract: An air-permeability measuring apparatus for textiles includes a measuring fork having first and second rigid legs disposed in parallel overlying relations. A first double pipe stub is displacably mounted to the first leg and has inner and outer stub parts providing an inner flow channel and an annular flow channel. A second double pipe stub is mounted into the second leg and includes inner and outer stub parts providing a second inner flow channel and a second annular flow channel. The double pipe stubs are coaxial and the first double pipe stub is adapted for being displaced between an insert position and a clamping position and in the clamping position the inner and annular flow channels are aligned and communicate. A pipe extends from each of the second inner and annular flow channels and the pipes are connected to an exhauster which exerts a vacuum on the inner and annular flow channels and thereby induces air flow therethrough.