Abstract: A valve device includes: a housing; a float valve; and a float valve support portion. The float valve support portion includes a support wall, a side wall, a first slit formed in the support wall, a second slit formed in the side wall, and an elastic piece defined by the first slit and the second slit. The elastic piece includes a first extending portion extending along the side wall, and a second extending portion extending from the first extending portion and capable of coming into contact with a bottom surface of the float valve.

Abstract: There is provided a fill-up restriction valve including: a housing; and a float valve. The housing includes a housing body including a body-side peripheral wall, and a lower cap including a cap-side peripheral wall, the lower cap being installed to a lower side of the housing body by a joint portion. The joint portion includes an annular groove, an insertion wall portion, and an annular protrusion formed on one of the insertion wall portion and the annular groove, or an annular seal member disposed between the insertion wall portion and the annular groove. The annular protrusion or the annular seal member is configured to be in pressure-contact with the annular groove and the insertion wall portion in a state where the insertion wall portion is inserted into the annular groove.