Jean-François Pilâtre de Rozier (30 March 1754 - 15 June 1785) was a French chemistry and physics teacher, and one of the first pioneers of aviation. His balloon crashed near Wimereux in the Pas-de-Calais during an attempt to fly across the English Channel, and he and his companion, Pierre Romain, became the first known victims of an air crash.

He was born in Metz, the fourth son of Magdeleine Wilmard and Mathurin Pilastre, known as "du Rosier", a former soldier who became an innkeeper. His interests in the chemistry of drugs had been awakened in the military hospital of Metz, an important garrison town on the border of France. He made his way to Paris at the age of 18, then taught physics and chemistry at the Academy in Reims, which brought him to the attention of Monsieur, the comte d'Artois, brother of King Louis XVI. He returned to Paris, where he was put in charge of Monsieur's cabinet of natural history and made him a valet de chambre to Monsieur's wife, Madame, which brought him his ennobled name, Pilâtre de Rozier. He opened his own museum in the Marais quarter of Paris on 11 December 1781, where he undertook experiments in physics and provided demonstrations to nobles. He researched the new field of gases and invented a respirator.

In June 1783, he witnessed the first balloon flight of the Montgolfier brothers. On 19 September, he assisted with the untethered flight of a sheep, a cockerel and a duck from the front courtyard of the Palace of Versailles. After a variety of tests in October, he made the first manned free flight in history on 21 November 1783, accompanied by the ambitious Marquis d'Arlandes. During the 25-minute flight using a Montgolfier hot air balloon, they traveled 12 kilometres from the Château de la Muette to the Butte-aux-Cailles, then in the outskirts of Paris, attaining an altitude of 3,000 feet.

Along with Joseph Montgolfier, he was one of six passengers on a second flight on 19 January 1784, with a huge Montgolfier balloon Le Flesselles launched from Lyon. Four French nobles paid for the trip, including a prince. Several difficulties had to be overcome. The wallpaper became wet because of extreme weather conditions. The top of the balloon was made of sheep- or buckskin. The air was heated by wood in an iron stove: to start, the straw was set on fire with brandy. (In other tests charcoal or potatoes were used). The balloon had a volume of approximately 23,000 m³, over 10 times that of the first flight, but only flew a short distance. The spectators kneeled down when the balloon came down too quickly. That evening the aeronauts were celebrated after listening to Gluck's opera, Iphigénie en Tauride.

Rosier took part in a further flight on 23 June 1784, in a modified version of the Montgolfier's first balloon christened La Marie-Antoinette after the Queen, which took off in front of the King of France and King Gustav III of Sweden. Together with Joseph Proust, the balloon flew north at an altitude of approximately 3,000 metres, above the clouds. They travelled 52 km in 45 minutes before cold and turbulence forced them to descend past Luzarches, between Coye et Orry-la-Ville, near the Chantilly forest. They set records for speed, altitude and distance travelled.