The Lioré et Olivier Leo H-15 was a French twelve-seat civil flying boat, flown in a national contest in 1926.

Compared with similar landplane competitions, few manufacturers offered a candidate; at the trials, held in July and August only the Lioré et Olivier LeO H-15 and the SPCA Météore 63 took part.

The pilot was positioned in an open cockpit just ahead of the leading edge of the wing and a "luxurious" passenger cabin, accommodating twelve, was accessed via a hatch in the nose.

On each side a stabilizing float was mounted below the lower wing on extensions of the outer interplane struts, strengthened with another, inward pair.

The Météore out-performed the LeO in the commercial flight tests and was judged safer and more comfortable for the passengers, though its take-offs took longer, it climbed more slowly and was less seaworthy.