A vessel mouth gasket unit 32 is fitted around the outer periphery of a valve body 2 which is internally formed with a filled liquid passage 4. A first gasket 38 having a smaller diameter and a second gasket 40 having a larger diameter is mounted on the lower surface of the unit 32. The filling valve comprises a liquid valve opening and closing air cylinder 16 which opens and closes a liquid valve 8 disposed in the filled liquid passage 4, and a vessel mouth gasket auxiliary air cylinder 42 which urges the unit 32 downward. The valve body 2 has an outer diameter D0 which is greater than the aperture diameter D1 of the bottle-like first type vessel B and less than the aperture diameter D2 of the second type vessel C having a larger aperture such as a canister. An operating pressure of the auxiliary air cylinder 42 is controllable and the filling operation takes place by urging the gasket 38 against the first vessel B with a low load and by urging the gasket 40 against the second type vessel C with a high load. The filling valve enables a combined use for filling the bottle-like first type vessel B and the second type vessel C having a larger aperture diameter such as a canister without requiring a replacement of parts. <IMAGE>
