Les Frères Robert are two French brothers.

Anne-Jean Robert (1758–1820) and Nicolas-Louis Robert (1760–1820) are the engineers who build the world's first hydrogen balloon for professor Jacques Charles; which flies from central Paris on August 27, 1783.

They go on to build the world's first manned hydrogen balloon, and on December 1, 1783, Nicolas-Louis accompanies Jacques Charles on a two-hour, five-minute flight.

Their barometer and thermometer made it the first balloon flight to provide meteorological measurements of the atmosphere above the Earth's surface.

The brothers subsequently experiment with an elongated elliptical shape for the hydrogen envelope in a balloon they attempt to power and steer by means of oars and umbrellas.

In September 1784 the brothers fly 186 km from Paris to Beuvry, the world's first flight of more than 100 kilometers.