PURPOSE: To constitute a hydroplane for leisure small and light.

CONSTITUTION: Flight controls 4, 5, a crew seat 6, a propeller 10 and a variable vertical tail 12 are provided on a hull 1 with a aerofoil section. A main wing 2 is constituted by coating a frame 18 with cloth like wing skin 19, and a float 3 is built up by enveloping a ski shape sliding plate 30 and an air bladder 33 in float skin 36, and by providing connecting members 31, 32 which penetrate from the sliding plate 30 to the air bladder 33 and the float skin. One-side ends of front and rear beams 15, 16 of the main wing 2 are connected to the hull 1 and other edges are connected to the float 3 by means of a skin connecting device 40.