To make comfortable the internal space of a small boat by providing a table plate body detachably engaged and supported via a support means at least at one position near the top of port and starboard air barrels.

The front and rear parts of an air boat 1 surrounded with an air barrel 2 are provided with seating plate bodies 4 and 4'. A table plate body 5 is provided between the seating plate bodies 4 and 4' near the top of a port and starboard air barrels 2a via a support member 6. More particularly, the forward end part of the projection part 6a of the support member 6 is inserted into the space formed out of an L-shaped recessed part 5' formed at the right and left end lower part of the table plate body 5 and the table plate body 5. For forming the support member 6, a sheet material is folded into two along a lengthwise axis and a long side is folded back for forming a projection part 6a. A rope or a plastic rod is inserted in the folded part, thereby forming a rib 6b at the end of the projection part 6a.